Yesterday, I awoke with the following thought:

Let's imagine Computers A and B have identical specs and are both scheduled to run an algorithm that would usually take one year at time T, with the A computer being accelerated to 0.5c at that time (or anything c). Both are configured to send the results to a central computer automatically.

From my perspective, would A complete processing first?

Would we be able to pick up A's broadcast?

Would it make a difference if A was traveling in a straight line, circling a planet, or even orbiting a star system?

Is it possible to speed up a computer enough that it can "compress time" on a machine like the LHC?

I apologize if this question is inappropriate for this group; I'm sure someone has asked it, but I'm not sure where to seek for the answer—I'm new to all things physics.

On 04-May-22 10:55 am, Mohammad Halai wrote:
> Yesterday, I awoke with the following thought:
>
> Let's imagine Computers A and B have identical specs and are both scheduled to run an algorithm that would usually take one year at time T, with the A computer being accelerated to 0.5c at that time (or anything c). Both are configured to send the results to a central computer automatically.
>
>
>
> From my perspective, would A complete processing first?

If B stays with you, you will always get the results from B before you
get the results from A.

Sylvia.

On Tue, 3 May 2022 17:55:23 -0700 (PDT), Mohammad Halai
<mohal3535@ugcloud.ca> wrote:

>Yesterday, I awoke with the following thought:
>
>Let's imagine Computers A and B have identical specs and are both scheduled to run an algorithm that would usually take one year at time T, with the A computer being accelerated to 0.5c at that time (or anything c). Both are configured to send the results to a central computer automatically.
>
>
>
>From my perspective, would A complete processing first?
>
>Would we be able to pick up A's broadcast?
>
>Would it make a difference if A was traveling in a straight line, circling a planet, or even orbiting a star system?
>
>Is it possible to speed up a computer enough that it can "compress time" on a machine like the LHC?
>
>I apologize if this question is inappropriate for this group; I'm sure someone has asked it, but I'm not sure where to seek for the answer—I'm new to all things physics.

That is basically the twins paradox:

https://en.wikipedia.org/wiki/Twin_paradox

The one who traveled aged (and calculated) slower.

--

If a man will begin with certainties, he shall end with doubts,
but if he will be content to begin with doubts he shall end in certainties.
Francis Bacon

On Tuesday, May 3, 2022 at 8:58:50 p.m. UTC-4, Sylvia Else wrote:
> On 04-May-22 10:55 am, Mohammad Halai wrote:
> > Yesterday, I awoke with the following thought:
> >
> > Let's imagine Computers A and B have identical specs and are both scheduled to run an algorithm that would usually take one year at time T, with the A computer being accelerated to 0.5c at that time (or anything c). Both are configured to send the results to a central computer automatically.
> >
> >
> >
> > From my perspective, would A complete processing first?
> If B stays with you, you will always get the results from B before you
> get the results from A.
>
>
> Sylvia.
Hi Sylvia,

I could argue that my accelerating computer 'loses time' thus its clock moves slower. Computers ultimately work on clock cycles. Thus it is fair to say that, as its clocking is ticking slower -- from my POV-- the computer on my desk will finish first?

Mohammad Halai <mohal3535@ugcloud.ca> wrote in
news:20c1a94c-7c6a-40fc-bc43-deffbfa8ee2dn@googlegroups.com:

> Yesterday, I awoke with the following thought:
>
> Let's imagine Computers A and B have identical specs and are both
> scheduled to run an algorithm that would usually take one year at
> time T, with the A computer being accelerated to 0.5c at that time
> (or anything c). Both are configured to send the results to a
> central computer automatically.
>
>
>
> From my perspective, would A complete processing first?
>
> Would we be able to pick up A's broadcast?
>
> Would it make a difference if A was traveling in a straight line,
> circling a planet, or even orbiting a star system?
>
> Is it possible to speed up a computer enough that it can "compress
> time" on a machine like the LHC?
>
> I apologize if this question is inappropriate for this group; I'm
> sure someone has asked it, but I'm not sure where to seek for the
> answer—I'm new to all things physics.
>

The speed at which you are moving does not change the speed at which
the computer in your phone does its processing compared to a
stationary phone. The bits toggle at the same rate in both.

On 5/3/2022 5:55 PM, Mohammad Halai wrote:
> Yesterday, I awoke with the following thought:
>
> Let's imagine Computers A and B have identical specs and are both scheduled
> to run an algorithm that would usually take one year at time T, with the A
> computer being accelerated to 0.5c at that time (or anything c). Both are
> configured to send the results to a central computer automatically.

So, that "central" computer is following A at 0.25c?
Do you *imagine* the transport delays from each are zero?
(i.e., you've not thought through your initial hypothesis)

> From my perspective, would A complete processing first?

And where, exactly, are *you*?

> Would we be able to pick up A's broadcast?

And where are *we*? At what fraction of c will A's broadcast occur?

> Would it make a difference if A was traveling in a straight line, circling a
> planet, or even orbiting a star system?
>
> Is it possible to speed up a computer enough that it can "compress time" on
> a machine like the LHC?
>
> I apologize if this question is inappropriate for this group; I'm sure
> someone has asked it, but I'm not sure where to seek for the answer—I'm new
> to all things physics.

The whole point of relativity is you can't be in two places at once -- so
there is no real way to compare "there1" and "there2", while they are
separated in space (and, thus, time).

Some years ago, Hawking presented an experiment in time dilation, here,
as part of the "Genius" TV series.

<http://leapsecond.com/great2016a/>
<http://leapsecond.com/great2016a/photos.htm>

It's really amusing when you see such esoteric bits of science actually
*work* as predicted!

On 04/05/2022 02:09, Mohammad Halai wrote:
> On Tuesday, May 3, 2022 at 8:58:50 p.m. UTC-4, Sylvia Else wrote:
>> On 04-May-22 10:55 am, Mohammad Halai wrote:
>>> Yesterday, I awoke with the following thought:
>>>
>>> Let's imagine Computers A and B have identical specs and are both
>>> scheduled to run an algorithm that would usually take one year at
>>> time T, with the A computer being accelerated to 0.5c at that
>>> time (or anything c). Both are configured to send the results to
>>> a central computer automatically.

>>> From my perspective, would A complete processing first?
>> If B stays with you, you will always get the results from B before
>> you get the results from A.
>
> I could argue that my accelerating computer 'loses time' thus its
> clock moves slower. Computers ultimately work on clock cycles. Thus
> it is fair to say that, as its clocking is ticking slower -- from my
> POV-- the computer on my desk will finish first?

The twin that travels at relativistic speed always returns younger than
the stay at home. It is quite likely that if we ever do develop space
vehicles capable of true relativistic speeds the first one to set off
will be quickly overtaken by later models (who will also return first).

There is an interesting corollary to this in the real world for absolute
cutting edge hefty computing problems like ab initio computation of the
masses of fundamental practicals and the like.

If your problem will take more than 2 years to execute on currently
available bleeding edge hardware the quickest way to get your results is
to do something else for 18 months and only then run the program!

ISTR the original quote suggests going to the beach and surfing.

--
Regards,
Martin Brown

On 5/4/2022 12:59 AM, Martin Brown wrote:
> There is an interesting corollary to this in the real world for absolute
> cutting edge hefty computing problems like ab initio computation of the masses
> of fundamental practicals and the like.

It needn't be "bleeding edge" but, rather, any design that is "up against the
stops" imposed by it's design criteria (e.g., cost limitations).

> If your problem will take more than 2 years to execute on currently available
> bleeding edge hardware the quickest way to get your results is to do something
> else for 18 months and only then run the program!

The more practical corollary (for those of us that build hardware devices)
is not to dick around with minor optimizations unless they provide ~2X
"performance" (for some definition of "performance") increase.

In day-to-day terms, that means:
- delay hardware finalization
- write portable code (so you can change processors easily)
- automate testing (so you can rerun test suites on other toolchains)
- avoid crippling a design by limiting it to "today's" technology

In my case, I use three different compiler families (i.e., not gcc
with three different back ends!) on three different hardware
platforms (SPARC, x86 and ARM) and implement the "processor choice"
as a hierarchical block in the (SBC) design so I can replace it
easily. This also means taking deliberate care to keep the I/O
system very generic so it doesn't rely on any exotic parts or
peculiarities of a specific processor/-family. (I have a whole
suite of compilers/emulators to verify the performance of a particular
I/O subsystem)

Every ~18 months, I get the opportunity to decide if I want to lower
the product cost (to capitalize on technological advances) *or*
increase the capabilities of the hardware. It's intoxicating! :>

> ISTR the original quote suggests going to the beach and surfing.

Martin Brown wrote:
> On 04/05/2022 02:09, Mohammad Halai wrote:
>> On Tuesday, May 3, 2022 at 8:58:50 p.m. UTC-4, Sylvia Else wrote:
>>> On 04-May-22 10:55 am, Mohammad Halai wrote:
>>>> Yesterday, I awoke with the following thought:
>>>>
>>>> Let's imagine Computers A and B have identical specs and are
>>>> both scheduled to run an algorithm that would usually take one
>>>> year at time T, with the A computer being accelerated to 0.5c
>>>> at that time (or anything c). Both are configured to send the
>>>> results to a central computer automatically.
>
>>>> From my perspective, would A complete processing first?
>>> If B stays with you, you will always get the results from B
>>> before you get the results from A.
>>
>> I could argue that my accelerating computer 'loses time' thus its
>> clock moves slower. Computers ultimately work on clock cycles.
>> Thus it is fair to say that, as its clocking is ticking slower --
>> from my POV-- the computer on my desk will finish first?
>
> The twin that travels at relativistic speed always returns younger
> than the stay at home. It is quite likely that if we ever do develop
> space vehicles capable of true relativistic speeds the first one to
> set off will be quickly overtaken by later models (who will also
> return first).

>
> There is an interesting corollary to this in the real world for
> absolute cutting edge hefty computing problems like ab initio
> computation of the masses of fundamental practicals and the like.
>
> If your problem will take more than 2 years to execute on currently
> available bleeding edge hardware the quickest way to get your results
> is to do something else for 18 months and only then run the program!
>
> ISTR the original quote suggests going to the beach and surfing.

Somebody wrote a paper like that 30 or so years ago, based on
algorithmic complexity and Moore's Law, that gave a formula for when one
should begin a computation in order to finish fastest.

Fun paper--I should try pulling it up sometime.

Cheers

Phil Hobbs
>

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

On Tuesday, May 3, 2022 at 9:09:51 PM UTC-4, moha...@ugcloud.ca wrote:
> On Tuesday, May 3, 2022 at 8:58:50 p.m. UTC-4, Sylvia Else wrote:
> > On 04-May-22 10:55 am, Mohammad Halai wrote:
> > > Yesterday, I awoke with the following thought:
> > >
> > > Let's imagine Computers A and B have identical specs and are both scheduled to run an algorithm that would usually take one year at time T, with the A computer being accelerated to 0.5c at that time (or anything c). Both are configured to send the results to a central computer automatically.
> > >
> > >
> > >
> > > From my perspective, would A complete processing first?
> > If B stays with you, you will always get the results from B before you
> > get the results from A.
> >
> >
> > Sylvia.
> Hi Sylvia,
>
> I could argue that my accelerating computer 'loses time' thus its clock moves slower. Computers ultimately work on clock cycles. Thus it is fair to say that, as its clocking is ticking slower -- from my POV-- the computer on my desk will finish first?

Yes. This is not a matter of speed, since speed is simply relative. It is a matter of acceleration which only one experiences. Unfortunately for scientists wanting their results faster, the accelerating computer is the slow one.

I'm not going to deal with any of the issues of getting the results, since that is an even more sticky wicket and does not change the basic issue of acceleration resulting in time dilation.

The only way to make this work to get faster computing, is for the scientist to be the one accelerating, which slows his own clock, so he returns sooner (by his clock) and the computations are complete. Meanwhile, everything else unaccelerated has also moved on in time without the scientist, like cities and people. But if the scientist doesn't have anything to do for a year, a tour of the solar system at 0.9 times the speed of light might be a fun thing to do while waiting and it won't be so long this way. A perk of being a scientist.

--

Rick C.

- Get 1,000 miles of free Supercharging
- Tesla referral code - https://ts.la/richard11209

On Tuesday, May 3, 2022 at 11:00:07 PM UTC-4, bill....@ieee.org wrote:
> On Wednesday, May 4, 2022 at 10:55:28 AM UTC+10, moha...@ugcloud.ca wrote:
> > Yesterday, I awoke with the following thought:
> >
> > Let's imagine Computers A and B have identical specs and are both scheduled to run an algorithm that would usually take one year at time T, with the A computer being accelerated to 0.5c at that time (or anything c). Both are configured to send the results to a central computer automatically.
> >
> > From my perspective, would A complete processing first?
> >
> > Would we be able to pick up A's broadcast?
> >
> > Would it make a difference if A was traveling in a straight line, circling a planet, or even orbiting a star system?
> >
> > Is it possible to speed up a computer enough that it can "compress time" on a machine like the LHC?
> >
> > I apologize if this question is inappropriate for this group; I'm sure someone has asked it, but I'm not sure where to seek for the answer—I'm new to all things physics.
> The question is close enough to one that has been subject to experimental test - admittedly with atomic clocks rather than computers
>
> https://en.wikipedia.org/wiki/Hafele%E2%80%93Keating_experiment
>
> The results were to some extent confounded by the fact that both traveling clocks were higher than the clock that stayed put on the ground, which meant that it had more gravitational red shift than they had, but the experimental design made that relatively easy to sort out.

"Relatively easy"? Is that a pun?

--

Rick C.

+ Get 1,000 miles of free Supercharging
+ Tesla referral code - https://ts.la/richard11209

On Wednesday, May 4, 2022 at 1:35:57 AM UTC-4, DecadentLinux...@decadence.org wrote:
> Mohammad Halai <moha...@ugcloud.ca> wrote in
> news:20c1a94c-7c6a-40fc...@googlegroups.com:
> > Yesterday, I awoke with the following thought:
> >
> > Let's imagine Computers A and B have identical specs and are both
> > scheduled to run an algorithm that would usually take one year at
> > time T, with the A computer being accelerated to 0.5c at that time
> > (or anything c). Both are configured to send the results to a
> > central computer automatically.
> >
> >
> >
> > From my perspective, would A complete processing first?
> >
> > Would we be able to pick up A's broadcast?
> >
> > Would it make a difference if A was traveling in a straight line,
> > circling a planet, or even orbiting a star system?
> >
> > Is it possible to speed up a computer enough that it can "compress
> > time" on a machine like the LHC?
> >
> > I apologize if this question is inappropriate for this group; I'm
> > sure someone has asked it, but I'm not sure where to seek for the
> > answer—I'm new to all things physics.
> >
> The speed at which you are moving does not change the speed at which
> the computer in your phone does its processing compared to a
> stationary phone. The bits toggle at the same rate in both.

Bzzzt! Sorry, wrong answer, even if it is technically correct. You didn't read the problem statement. "the A computer being accelerated to 0.5c" is the part you missed or ignored.

--

Rick C.

-- Get 1,000 miles of free Supercharging
-- Tesla referral code - https://ts.la/richard11209

On Thursday, May 5, 2022 at 2:12:46 AM UTC-4, bill....@ieee.org wrote:
> On Thursday, May 5, 2022 at 9:36:25 AM UTC+10, Ricky wrote:
> > On Wednesday, May 4, 2022 at 1:35:57 AM UTC-4, DecadentLinux...@decadence.org wrote:
> > > Mohammad Halai <moha...@ugcloud.ca> wrote in
> > > news:20c1a94c-7c6a-40fc...@googlegroups.com:
> > > > Yesterday, I awoke with the following thought:
> > > >
> > > > Let's imagine Computers A and B have identical specs and are both
> > > > scheduled to run an algorithm that would usually take one year at
> > > > time T, with the A computer being accelerated to 0.5c at that time
> > > > (or anything c). Both are configured to send the results to a
> > > > central computer automatically.
> > > >
> > > >
> > > >
> > > > From my perspective, would A complete processing first?
> > > >
> > > > Would we be able to pick up A's broadcast?
> > > >
> > > > Would it make a difference if A was traveling in a straight line,
> > > > circling a planet, or even orbiting a star system?
> > > >
> > > > Is it possible to speed up a computer enough that it can "compress
> > > > time" on a machine like the LHC?
> > > >
> > > > I apologize if this question is inappropriate for this group; I'm
> > > > sure someone has asked it, but I'm not sure where to seek for the
> > > > answer—I'm new to all things physics.
> > > >
> > > The speed at which you are moving does not change the speed at which
> > > the computer in your phone does its processing compared to a
> > > stationary phone. The bits toggle at the same rate in both.
> > Bzzzt! Sorry, wrong answer, even if it is technically correct. You didn't read the problem statement. "the A computer being accelerated to 0.5c" is the part you missed or ignored.
> It isn't even technically correct. Special relativity points out that a moving phone is going to be clocked more slowly than a stationary phone. Acceleration is indistinguishable from gravity, so general relativity requires you to pay attention to the acceleration as well, but gravitational red-shift is a different thing from Lorentz time-dilation.

Not sure what you mean about the moving vs. stationary clocks. I suppose I did not explain adequately. Since constant motion is purely relative, each clock is *observed* to be slower by the observer in the other time frame. So clearly, it makes no sense to talk about one clock actually running slower due to constant motion. It's just an effect of observation, with no actual change in time elapsing.

When one observer experiences acceleration, by either actual acceleration or a gravitational field, the effects are not relative, but absolute. So one observer does experience time differently as illustrated in the twin paradox.

From Wikipedia

Reciprocity
Given a certain frame of reference, and the "stationary" observer described earlier, if a second observer accompanied the "moving" clock, each of the observers would perceive the other's clock as ticking at a slower rate than their own local clock, due to them both perceiving the other to be the one that is in motion relative to their own stationary frame of reference.

Common sense would dictate that, if the passage of time has slowed for a moving object, said object would observe the external world's time to be correspondingly sped up. Counterintuitively, special relativity predicts the opposite. When two observers are in motion relative to each other, each will measure the other's clock slowing down, in concordance with them being in motion relative to the observer's frame of reference.

So what point are you trying to make?

--

Rick C.

-+ Get 1,000 miles of free Supercharging
-+ Tesla referral code - https://ts.la/richard11209

On 04/05/2022 08:59, Martin Brown wrote:

<snip>
>
> The twin that travels at relativistic speed always returns younger than
> the stay at home. It is quite likely that if we ever do develop space
> vehicles capable of true relativistic speeds the first one to set off
> will be quickly overtaken by later models (who will also return first).

The really difficult problem is how to calculate the astronaut's pay
when they return.

--
Cheers
Clive

Clive Arthur <clive@nowaytoday.co.uk> wrote in
news:t50m0b$l5i$1@dont-email.me:

> On 04/05/2022 08:59, Martin Brown wrote:
>
> <snip>
>>
>> The twin that travels at relativistic speed always returns
>> younger than the stay at home. It is quite likely that if we ever
>> do develop space vehicles capable of true relativistic speeds the
>> first one to set off will be quickly overtaken by later models
>> (who will also return first).
>
> The really difficult problem is how to calculate the astronaut's
> pay when they return.
>

By the time they return, society will have moved to cashless system.
Problem solved, they get nothing.

On Thursday, May 5, 2022 at 10:34:27 AM UTC-4, bill....@ieee.org wrote:
> On Friday, May 6, 2022 at 12:01:05 AM UTC+10, Ricky wrote:
> > On Thursday, May 5, 2022 at 2:12:46 AM UTC-4, bill....@ieee.org wrote:
> > > On Thursday, May 5, 2022 at 9:36:25 AM UTC+10, Ricky wrote:
> > > > On Wednesday, May 4, 2022 at 1:35:57 AM UTC-4, DecadentLinux...@decadence.org wrote:
> > > > > Mohammad Halai <moha...@ugcloud.ca> wrote in
> > > > > news:20c1a94c-7c6a-40fc...@googlegroups.com:
> <snip>
> > > > Bzzzt! Sorry, wrong answer, even if it is technically correct. You didn't read the problem statement. "the A computer being accelerated to 0.5c" is the part you missed or ignored.
> > > It isn't even technically correct. Special relativity points out that a moving phone is going to be clocked more slowly than a stationary phone. Acceleration is indistinguishable from gravity, so general relativity requires you to pay attention to the acceleration as well, but gravitational red-shift is a different thing from Lorentz time-dilation.
> >
> > Not sure what you mean about the moving vs. stationary clocks. I suppose I did not explain adequately.
> It's more that your explanation misses some of the detail and is inadequate that that extent.
> >Since constant motion is purely relative, each clock is *observed* to be slower by the observer in the other time frame. So clearly, it makes no sense to talk about one clock actually running slower due to constant motion. It's just an effect of observation, with no actual change in time elapsing..
> >
> > When one observer experiences acceleration, by either actual acceleration or a gravitational field, the effects are not relative, but absolute. So one observer does experience time differently as illustrated in the twin paradox.
> >
> > From Wikipedia
> >
> > Reciprocity
> > Given a certain frame of reference, and the "stationary" observer described earlier, if a second observer accompanied the "moving" clock, each of the observers would perceive the other's clock as ticking at a slower rate than their own local clock, due to them both perceiving the other to be the one that is in motion relative to their own stationary frame of reference.
> Also from Wikipedia
>
> https://en.wikipedia.org/wiki/Hafele%E2%80%93Keating_experiment
> > Common sense would dictate that, if the passage of time has slowed for a moving object, said object would observe the external world's time to be correspondingly sped up. Counterintuitively, special relativity predicts the opposite. When two observers are in motion relative to each other, each will measure the other's clock slowing down, in concordance with them being in motion relative to the observer's frame of reference.
> >
> > So what point are you trying to make?
> That there is experimental evidence that if you send an atomic clock around the earth in the same direction that the earth is spinning, it runs slower than one that has been sent around the earth in the opposite direction.Of course they both run a bit faster than the third atomic clock that stayed at home on the ground and was thus more red-shifted by the influence of the earth's gravitational field (which is weaker when you are up in an aircraft).
>
> Clearly both moving clocks were subjected to much the same accelerations every time their plane took off and landed - that won't be affected by the direction in which they flew around the world.
>
> The effects are separable. Looking up what "reciprocity" means seems to be a less useful exercise.

Ok, so you are talking about something different from the rest of us. Fine, glad we got that straight.

--

Rick C.

+- Get 1,000 miles of free Supercharging
+- Tesla referral code - https://ts.la/richard11209

On 05/05/2022 15:01, Ricky wrote:
> On Thursday, May 5, 2022 at 2:12:46 AM UTC-4, bill....@ieee.org
> wrote:
>> On Thursday, May 5, 2022 at 9:36:25 AM UTC+10, Ricky wrote:
>>> On Wednesday, May 4, 2022 at 1:35:57 AM UTC-4,
>>> DecadentLinux...@decadence.org wrote:
>>>> Mohammad Halai <moha...@ugcloud.ca> wrote in
>>>> news:20c1a94c-7c6a-40fc...@googlegroups.com:
>>>>> Yesterday, I awoke with the following thought:
>>>>>
>>>>> Let's imagine Computers A and B have identical specs and are
>>>>> both scheduled to run an algorithm that would usually take
>>>>> one year at time T, with the A computer being accelerated to
>>>>> 0.5c at that time (or anything c). Both are configured to
>>>>> send the results to a central computer automatically.
>>>>>
>>>>>
>>>>>
>>>>> From my perspective, would A complete processing first?
>>>>>
>>>>> Would we be able to pick up A's broadcast?
>>>>>
>>>>> Would it make a difference if A was traveling in a straight
>>>>> line, circling a planet, or even orbiting a star system?
>>>>>
>>>>> Is it possible to speed up a computer enough that it can
>>>>> "compress time" on a machine like the LHC?
>>>>>
>>>>> I apologize if this question is inappropriate for this group;
>>>>> I'm sure someone has asked it, but I'm not sure where to seek
>>>>> for the answer—I'm new to all things physics.
>>>>>
>>>> The speed at which you are moving does not change the speed at
>>>> which the computer in your phone does its processing compared
>>>> to a stationary phone. The bits toggle at the same rate in
>>>> both.
>>> Bzzzt! Sorry, wrong answer, even if it is technically correct.
>>> You didn't read the problem statement. "the A computer being
>>> accelerated to 0.5c" is the part you missed or ignored.
>> It isn't even technically correct. Special relativity points out
>> that a moving phone is going to be clocked more slowly than a
>> stationary phone. Acceleration is indistinguishable from gravity,
>> so general relativity requires you to pay attention to the
>> acceleration as well, but gravitational red-shift is a different
>> thing from Lorentz time-dilation.
>
> Not sure what you mean about the moving vs. stationary clocks. I
> suppose I did not explain adequately. Since constant motion is
> purely relative, each clock is *observed* to be slower by the
> observer in the other time frame. So clearly, it makes no sense to
> talk about one clock actually running slower due to constant motion.
> It's just an effect of observation, with no actual change in time
> elapsing.

There are some cosmic ray muons hitting the ground that would disagree
with your perverse and confused interpretation of special relativity.

https://ph.qmul.ac.uk/sites/default/files/Engagement/Muons%20and%20Special%20Relativity.pdf

Moving clocks appear to tick more slowly the faster that they are
moving. In their rest frame cosmic ray generated muons have a half life
of about 2.2us which isn't long enough for them to reach the ground even
at nearly the speed of light.

It is precisely *because* they are moving so quickly that they *DO* last
much longer in our almost stationary observers rest frame on the Earth.

Their clock time is subject to a gamma factor of about 40x.

> When one observer experiences acceleration, by either actual
> acceleration or a gravitational field, the effects are not relative,
> but absolute. So one observer does experience time differently as
> illustrated in the twin paradox.
>
> From Wikipedia
>
> Reciprocity Given a certain frame of reference, and the "stationary"
> observer described earlier, if a second observer accompanied the
> "moving" clock, each of the observers would perceive the other's
> clock as ticking at a slower rate than their own local clock, due to
> them both perceiving the other to be the one that is in motion
> relative to their own stationary frame of reference.

It is possible to derive the classic SR Lorentz transformations by very
careful consideration of the mutual events of two metre rules as
measured in their respective rest frames passing each other at a speed v
enough for relativistic corrections to apply by invoking reciprocity.

> So what point are you trying to make?

I think it is more appropriate to ask you that question.

--
Regards,
Martin Brown

On Sun, 8 May 2022 21:28:52 +0100, Martin Brown
<'''newspam'''@nonad.co.uk> wrote:

>On 05/05/2022 15:01, Ricky wrote:
>> On Thursday, May 5, 2022 at 2:12:46 AM UTC-4, bill....@ieee.org
>> wrote:
>>> On Thursday, May 5, 2022 at 9:36:25 AM UTC+10, Ricky wrote:
>>>> On Wednesday, May 4, 2022 at 1:35:57 AM UTC-4,
>>>> DecadentLinux...@decadence.org wrote:
>>>>> Mohammad Halai <moha...@ugcloud.ca> wrote in
>>>>> news:20c1a94c-7c6a-40fc...@googlegroups.com:
>>>>>> Yesterday, I awoke with the following thought:
>>>>>>
>>>>>> Let's imagine Computers A and B have identical specs and are
>>>>>> both scheduled to run an algorithm that would usually take
>>>>>> one year at time T, with the A computer being accelerated to
>>>>>> 0.5c at that time (or anything c). Both are configured to
>>>>>> send the results to a central computer automatically.
>>>>>>
>>>>>>
>>>>>>
>>>>>> From my perspective, would A complete processing first?
>>>>>>
>>>>>> Would we be able to pick up A's broadcast?
>>>>>>
>>>>>> Would it make a difference if A was traveling in a straight
>>>>>> line, circling a planet, or even orbiting a star system?
>>>>>>
>>>>>> Is it possible to speed up a computer enough that it can
>>>>>> "compress time" on a machine like the LHC?
>>>>>>
>>>>>> I apologize if this question is inappropriate for this group;
>>>>>> I'm sure someone has asked it, but I'm not sure where to seek
>>>>>> for the answer—I'm new to all things physics.
>>>>>>
>>>>> The speed at which you are moving does not change the speed at
>>>>> which the computer in your phone does its processing compared
>>>>> to a stationary phone. The bits toggle at the same rate in
>>>>> both.
>>>> Bzzzt! Sorry, wrong answer, even if it is technically correct.
>>>> You didn't read the problem statement. "the A computer being
>>>> accelerated to 0.5c" is the part you missed or ignored.
>>> It isn't even technically correct. Special relativity points out
>>> that a moving phone is going to be clocked more slowly than a
>>> stationary phone. Acceleration is indistinguishable from gravity,
>>> so general relativity requires you to pay attention to the
>>> acceleration as well, but gravitational red-shift is a different
>>> thing from Lorentz time-dilation.
>>
>> Not sure what you mean about the moving vs. stationary clocks. I
>> suppose I did not explain adequately. Since constant motion is
>> purely relative, each clock is *observed* to be slower by the
>> observer in the other time frame. So clearly, it makes no sense to
>> talk about one clock actually running slower due to constant motion.
>> It's just an effect of observation, with no actual change in time
>> elapsing.
>
>There are some cosmic ray muons hitting the ground that would disagree
>with your perverse and confused interpretation of special relativity.
>
>https://ph.qmul.ac.uk/sites/default/files/Engagement/Muons%20and%20Special%20Relativity.pdf
>
>Moving clocks appear to tick more slowly the faster that they are
>moving. In their rest frame cosmic ray generated muons have a half life
>of about 2.2us which isn't long enough for them to reach the ground even
>at nearly the speed of light.
>
>It is precisely *because* they are moving so quickly that they *DO* last
>much longer in our almost stationary observers rest frame on the Earth.
>
>Their clock time is subject to a gamma factor of about 40x.

I think the problem here is the conflict between two oft-heard
statements:

1. Velocity is relative - there is no such thing as a single fixed
coordinate system for the universe, so there cannot be such a thing a
as absolute velocity.

2. So local time in a moving platform (like a spaceship) passes
slower and slower the faster the platform is moving.

So in the twin paradox, given that velocity is relative, one ought to
be able to arbitrarily say that ship 2 is stationary, and ship 1 is
traveling at 0.9 C, or vice versa. So, how is it that one ages but
the other doesn't? By symmetry, they cannot differ.

What then breaks the symmetry? The obvious answer is the differences
in the acceleration histories of the two ships? How?

A clear answer might settle this debate thread.

Joe Gwinn

torsdag den 5. maj 2022 kl. 16.15.09 UTC+2 skrev Clive Arthur:
> On 04/05/2022 08:59, Martin Brown wrote:
>
> <snip>
> >
> > The twin that travels at relativistic speed always returns younger than
> > the stay at home. It is quite likely that if we ever do develop space
> > vehicles capable of true relativistic speeds the first one to set off
> > will be quickly overtaken by later models (who will also return first).
> The really difficult problem is how to calculate the astronaut's pay
> when they return.

just depend on agreeing whether you get paid for the hours worked,
or you get paid for the hours you couldn't do something else

On Sunday, May 8, 2022 at 4:29:00 PM UTC-4, Martin Brown wrote:
> On 05/05/2022 15:01, Ricky wrote:
> > On Thursday, May 5, 2022 at 2:12:46 AM UTC-4, bill....@ieee.org
> > wrote:
> >> On Thursday, May 5, 2022 at 9:36:25 AM UTC+10, Ricky wrote:
> >>> On Wednesday, May 4, 2022 at 1:35:57 AM UTC-4,
> >>> DecadentLinux...@decadence.org wrote:
> >>>> Mohammad Halai <moha...@ugcloud.ca> wrote in
> >>>> news:20c1a94c-7c6a-40fc...@googlegroups.com:
> >>>>> Yesterday, I awoke with the following thought:
> >>>>>
> >>>>> Let's imagine Computers A and B have identical specs and are
> >>>>> both scheduled to run an algorithm that would usually take
> >>>>> one year at time T, with the A computer being accelerated to
> >>>>> 0.5c at that time (or anything c). Both are configured to
> >>>>> send the results to a central computer automatically.
> >>>>>
> >>>>>
> >>>>>
> >>>>> From my perspective, would A complete processing first?
> >>>>>
> >>>>> Would we be able to pick up A's broadcast?
> >>>>>
> >>>>> Would it make a difference if A was traveling in a straight
> >>>>> line, circling a planet, or even orbiting a star system?
> >>>>>
> >>>>> Is it possible to speed up a computer enough that it can
> >>>>> "compress time" on a machine like the LHC?
> >>>>>
> >>>>> I apologize if this question is inappropriate for this group;
> >>>>> I'm sure someone has asked it, but I'm not sure where to seek
> >>>>> for the answer—I'm new to all things physics.
> >>>>>
> >>>> The speed at which you are moving does not change the speed at
> >>>> which the computer in your phone does its processing compared
> >>>> to a stationary phone. The bits toggle at the same rate in
> >>>> both.
> >>> Bzzzt! Sorry, wrong answer, even if it is technically correct.
> >>> You didn't read the problem statement. "the A computer being
> >>> accelerated to 0.5c" is the part you missed or ignored.
> >> It isn't even technically correct. Special relativity points out
> >> that a moving phone is going to be clocked more slowly than a
> >> stationary phone. Acceleration is indistinguishable from gravity,
> >> so general relativity requires you to pay attention to the
> >> acceleration as well, but gravitational red-shift is a different
> >> thing from Lorentz time-dilation.
> >
> > Not sure what you mean about the moving vs. stationary clocks. I
> > suppose I did not explain adequately. Since constant motion is
> > purely relative, each clock is *observed* to be slower by the
> > observer in the other time frame. So clearly, it makes no sense to
> > talk about one clock actually running slower due to constant motion.
> > It's just an effect of observation, with no actual change in time
> > elapsing.
> There are some cosmic ray muons hitting the ground that would disagree
> with your perverse and confused interpretation of special relativity.
>
> https://ph.qmul.ac.uk/sites/default/files/Engagement/Muons%20and%20Special%20Relativity.pdf
>
> Moving clocks appear to tick more slowly the faster that they are
> moving. In their rest frame cosmic ray generated muons have a half life
> of about 2.2us which isn't long enough for them to reach the ground even
> at nearly the speed of light.
>
> It is precisely *because* they are moving so quickly that they *DO* last
> much longer in our almost stationary observers rest frame on the Earth.

You can't even state the problem correctly. Our frame of reference is no more stationary than the muon. This is why it is impossible to define simultaneity under some conditions. In one frame of reference A precedes B, in another frame of reference B precedes A. There is no right answer just as there is no stationary frame of reference.

Please analyze the muon reaching the ground with the observer moving with the muon rather than on the ground.

> Their clock time is subject to a gamma factor of about 40x.
> > When one observer experiences acceleration, by either actual
> > acceleration or a gravitational field, the effects are not relative,
> > but absolute. So one observer does experience time differently as
> > illustrated in the twin paradox.
> >
> > From Wikipedia
> >
> > Reciprocity Given a certain frame of reference, and the "stationary"
> > observer described earlier, if a second observer accompanied the
> > "moving" clock, each of the observers would perceive the other's
> > clock as ticking at a slower rate than their own local clock, due to
> > them both perceiving the other to be the one that is in motion
> > relative to their own stationary frame of reference.
> It is possible to derive the classic SR Lorentz transformations by very
> careful consideration of the mutual events of two metre rules as
> measured in their respective rest frames passing each other at a speed v
> enough for relativistic corrections to apply by invoking reciprocity.
> > So what point are you trying to make?
> I think it is more appropriate to ask you that question.

I was discussing a topic. Was there something I said that you found unclear?

--

Rick C.

++ Get 1,000 miles of free Supercharging
++ Tesla referral code - https://ts.la/richard11209

On Sunday, May 8, 2022 at 9:04:08 PM UTC-4, bill....@ieee.org wrote:
> On Monday, May 9, 2022 at 7:39:36 AM UTC+10, Joe Gwinn wrote:
> > On Sun, 8 May 2022 21:28:52 +0100, Martin Brown <'''newspam'''@nonad.co..uk> wrote:
> > >On 05/05/2022 15:01, Ricky wrote:
> > >> On Thursday, May 5, 2022 at 2:12:46 AM UTC-4, bill....@ieee.org wrote:
> > >>> On Thursday, May 5, 2022 at 9:36:25 AM UTC+10, Ricky wrote:
> > >>>> On Wednesday, May 4, 2022 at 1:35:57 AM UTC-4, DecadentLinux...@decadence.org wrote:
> > >>>>> Mohammad Halai <moha...@ugcloud.ca> wrote in news:20c1a94c-7c6a-40fc...@googlegroups.com:
> <snip>
> > >>>>> The speed at which you are moving does not change the speed at
> > >>>>> which the computer in your phone does its processing compared
> > >>>>> to a stationary phone. The bits toggle at the same rate in
> > >>>>> both.
> > >>>> Bzzzt! Sorry, wrong answer, even if it is technically correct.
> > >>>> You didn't read the problem statement. "the A computer being
> > >>>> accelerated to 0.5c" is the part you missed or ignored.
> > >>> It isn't even technically correct. Special relativity points out
> > >>> that a moving phone is going to be clocked more slowly than a
> > >>> stationary phone. Acceleration is indistinguishable from gravity,
> > >>> so general relativity requires you to pay attention to the
> > >>> acceleration as well, but gravitational red-shift is a different
> > >>> thing from Lorentz time-dilation.
> > >>
> > >> Not sure what you mean about the moving vs. stationary clocks. I
> > >> suppose I did not explain adequately. Since constant motion is
> > >> purely relative, each clock is *observed* to be slower by the
> > >> observer in the other time frame. So clearly, it makes no sense to
> > >> talk about one clock actually running slower due to constant motion.
> > >> It's just an effect of observation, with no actual change in time
> > >> elapsing.
> > >
> > >There are some cosmic ray muons hitting the ground that would disagree
> > >with your perverse and confused interpretation of special relativity.
> > >
> > >https://ph.qmul.ac.uk/sites/default/files/Engagement/Muons%20and%20Special%20Relativity.pdf
> > >
> > >Moving clocks appear to tick more slowly the faster that they are
> > >moving. In their rest frame cosmic ray generated muons have a half life
> > >of about 2.2us which isn't long enough for them to reach the ground even
> > >at nearly the speed of light.
> > >
> > >It is precisely *because* they are moving so quickly that they *DO* last
> > >much longer in our almost stationary observers rest frame on the Earth..
> > >
> > >Their clock time is subject to a gamma factor of about 40x.
> > I think the problem here is the conflict between two oft-heard
> > statements:
> >
> > 1. Velocity is relative - there is no such thing as a single fixed
> > coordinate system for the universe, so there cannot be such a thing a
> > as absolute velocity.
> Actually there is - the microwave background defines a a zero velocity coordinate from which it looks essentially uniform in every direction.

I'm pretty sure that's a fallacy. Every point in the universe sees the entire rest of the universe expanding away from that point, including the microwave background. It should appear the same everywhere in the universe if you are referring to the extent of the red-shift. What do you mean exactly by "it looks essentially uniform"? Uniform in what aspect?

> It's a proxy for the "fixed stars" which is now the retreating galaxies.
> > 2. So local time in a moving platform (like a spaceship) passes
> > slower and slower the faster the platform is moving.
> >
> > So in the twin paradox, given that velocity is relative, one ought to
> > be able to arbitrarily say that ship 2 is stationary, and ship 1 is
> > traveling at 0.9 C, or vice versa. So, how is it that one ages but
> > the other doesn't? By symmetry, they cannot differ.
> >
> > What then breaks the symmetry? The obvious answer is the differences in the acceleration histories of the two ships? How?
> Integrating the acceleration gives you velocities.
> > A clear answer might settle this debate thread.

That's hard to do. When we consider the moving train analogy, that typically ignored the method of viewing what is happening on the other train. I expect this can complicate the matter as well.

--

Rick C.

--- Get 1,000 miles of free Supercharging
--- Tesla referral code - https://ts.la/richard11209

On Monday, May 9, 2022 at 1:07:29 AM UTC-4, bill....@ieee.org wrote:
> On Monday, May 9, 2022 at 1:17:48 PM UTC+10, Ricky wrote:
> > On Sunday, May 8, 2022 at 9:04:08 PM UTC-4, bill....@ieee.org wrote:
> > > On Monday, May 9, 2022 at 7:39:36 AM UTC+10, Joe Gwinn wrote:
> > > > On Sun, 8 May 2022 21:28:52 +0100, Martin Brown <'''newspam'''@nonad.co.uk> wrote:
> > > > >On 05/05/2022 15:01, Ricky wrote:
> > > > >> On Thursday, May 5, 2022 at 2:12:46 AM UTC-4, bill....@ieee.org wrote:
> > > > >>> On Thursday, May 5, 2022 at 9:36:25 AM UTC+10, Ricky wrote:
> > > > >>>> On Wednesday, May 4, 2022 at 1:35:57 AM UTC-4, DecadentLinux....@decadence.org wrote:
> > > > >>>>> Mohammad Halai <moha...@ugcloud.ca> wrote in news:20c1a94c-7c6a-40fc...@googlegroups.com:
> > > <snip>
> > > > >>>>> The speed at which you are moving does not change the speed at
> > > > >>>>> which the computer in your phone does its processing compared
> > > > >>>>> to a stationary phone. The bits toggle at the same rate in
> > > > >>>>> both.
> > > > >>>> Bzzzt! Sorry, wrong answer, even if it is technically correct.
> > > > >>>> You didn't read the problem statement. "the A computer being
> > > > >>>> accelerated to 0.5c" is the part you missed or ignored.
> > > > >>> It isn't even technically correct. Special relativity points out
> > > > >>> that a moving phone is going to be clocked more slowly than a
> > > > >>> stationary phone. Acceleration is indistinguishable from gravity,
> > > > >>> so general relativity requires you to pay attention to the
> > > > >>> acceleration as well, but gravitational red-shift is a different
> > > > >>> thing from Lorentz time-dilation.
> > > > >>
> > > > >> Not sure what you mean about the moving vs. stationary clocks. I
> > > > >> suppose I did not explain adequately. Since constant motion is
> > > > >> purely relative, each clock is *observed* to be slower by the
> > > > >> observer in the other time frame. So clearly, it makes no sense to
> > > > >> talk about one clock actually running slower due to constant motion.
> > > > >> It's just an effect of observation, with no actual change in time
> > > > >> elapsing.
> > > > >
> > > > >There are some cosmic ray muons hitting the ground that would disagree
> > > > >with your perverse and confused interpretation of special relativity.
> > > > >
> > > > >https://ph.qmul.ac.uk/sites/default/files/Engagement/Muons%20and%20Special%20Relativity.pdf
> > > > >
> > > > >Moving clocks appear to tick more slowly the faster that they are
> > > > >moving. In their rest frame cosmic ray generated muons have a half life
> > > > >of about 2.2us which isn't long enough for them to reach the ground even
> > > > >at nearly the speed of light.
> > > > >
> > > > >It is precisely *because* they are moving so quickly that they *DO* last
> > > > >much longer in our almost stationary observers rest frame on the Earth.
> > > > >
> > > > >Their clock time is subject to a gamma factor of about 40x.
> > > > I think the problem here is the conflict between two oft-heard
> > > > statements:
> > > >
> > > > 1. Velocity is relative - there is no such thing as a single fixed
> > > > coordinate system for the universe, so there cannot be such a thing a
> > > > as absolute velocity.
> > >
> > > Actually there is - the microwave background defines a a zero velocity coordinate from which it looks essentially uniform in every direction.
> >
> > I'm pretty sure that's a fallacy.
> It isn't.

Oh, but it is.

> > Every point in the universe sees the entire rest of the universe expanding away from that point, including the microwave background. It should appear the same everywhere in the universe if you are referring to the extent of the red-shift. What do you mean exactly by "it looks essentially uniform"? Uniform in what aspect?
> As soon as you start moving with respect to the rest of the universe the segment of the microwave background you are moving towards is Doppler shifted to a shorter wavelength, and the segment you are moving away from is Doppler-shifted to a longer wavelength.

So I can measure my speed through the ether? Wow! Too bad Michelson and Morley didn't know about this. Who has measured out speed through the microwave background? What is our speed relative to the universe?

Wow! What if the Universe is itself moving? Maybe the Universe is moving at some huge factor of the speed of light? That would be trippy!

> > > It's a proxy for the "fixed stars" which is now the retreating galaxies.
> > > > 2. So local time in a moving platform (like a spaceship) passes
> > > > slower and slower the faster the platform is moving.
> > > >
> > > > So in the twin paradox, given that velocity is relative, one ought to
> > > > be able to arbitrarily say that ship 2 is stationary, and ship 1 is
> > > > traveling at 0.9 C, or vice versa. So, how is it that one ages but
> > > > the other doesn't? By symmetry, they cannot differ.
> > > >
> > > > What then breaks the symmetry? The obvious answer is the differences in the acceleration histories of the two ships? How?
> > >
> > > Integrating the acceleration gives you velocities.
> >
> > > > A clear answer might settle this debate thread.
> >
> > That's hard to do. When we consider the moving train analogy, that typically ignored the method of viewing what is happening on the other train. I expect this can complicate the matter as well.
> If you are in the business of getting and staying confused, you can find a lot of stuff to get confused about.

Yeah, let us know how it works out for you.

--

Rick C.

--+ Get 1,000 miles of free Supercharging
--+ Tesla referral code - https://ts.la/richard11209

On Monday, May 9, 2022 at 1:19:02 AM UTC-4, bill....@ieee.org wrote:
> On Monday, May 9, 2022 at 1:09:39 PM UTC+10, Ricky wrote:
> > On Sunday, May 8, 2022 at 4:29:00 PM UTC-4, Martin Brown wrote:
> > > On 05/05/2022 15:01, Ricky wrote:
> > > > On Thursday, May 5, 2022 at 2:12:46 AM UTC-4, bill....@ieee.org
> > > > wrote:
> > > >> On Thursday, May 5, 2022 at 9:36:25 AM UTC+10, Ricky wrote:
> > > >>> On Wednesday, May 4, 2022 at 1:35:57 AM UTC-4,
> > > >>> DecadentLinux...@decadence.org wrote:
> > > >>>> Mohammad Halai <moha...@ugcloud.ca> wrote in
> > > >>>> news:20c1a94c-7c6a-40fc...@googlegroups.com:
> > > >>>>> Yesterday, I awoke with the following thought:
> > > >>>>>
> > > >>>>> Let's imagine Computers A and B have identical specs and are
> > > >>>>> both scheduled to run an algorithm that would usually take
> > > >>>>> one year at time T, with the A computer being accelerated to
> > > >>>>> 0.5c at that time (or anything c). Both are configured to
> > > >>>>> send the results to a central computer automatically.
> > > >>>>>
> > > >>>>>
> > > >>>>>
> > > >>>>> From my perspective, would A complete processing first?
> > > >>>>>
> > > >>>>> Would we be able to pick up A's broadcast?
> > > >>>>>
> > > >>>>> Would it make a difference if A was traveling in a straight
> > > >>>>> line, circling a planet, or even orbiting a star system?
> > > >>>>>
> > > >>>>> Is it possible to speed up a computer enough that it can
> > > >>>>> "compress time" on a machine like the LHC?
> > > >>>>>
> > > >>>>> I apologize if this question is inappropriate for this group;
> > > >>>>> I'm sure someone has asked it, but I'm not sure where to seek
> > > >>>>> for the answer—I'm new to all things physics.
> > > >>>>>
> > > >>>> The speed at which you are moving does not change the speed at
> > > >>>> which the computer in your phone does its processing compared
> > > >>>> to a stationary phone. The bits toggle at the same rate in
> > > >>>> both.
> > > >>> Bzzzt! Sorry, wrong answer, even if it is technically correct.
> > > >>> You didn't read the problem statement. "the A computer being
> > > >>> accelerated to 0.5c" is the part you missed or ignored.
> > > >> It isn't even technically correct. Special relativity points out
> > > >> that a moving phone is going to be clocked more slowly than a
> > > >> stationary phone. Acceleration is indistinguishable from gravity,
> > > >> so general relativity requires you to pay attention to the
> > > >> acceleration as well, but gravitational red-shift is a different
> > > >> thing from Lorentz time-dilation.
> > > >
> > > > Not sure what you mean about the moving vs. stationary clocks. I
> > > > suppose I did not explain adequately. Since constant motion is
> > > > purely relative, each clock is *observed* to be slower by the
> > > > observer in the other time frame. So clearly, it makes no sense to
> > > > talk about one clock actually running slower due to constant motion..
> > > > It's just an effect of observation, with no actual change in time
> > > > elapsing.
> > > There are some cosmic ray muons hitting the ground that would disagree
> > > with your perverse and confused interpretation of special relativity.
> > >
> > > https://ph.qmul.ac.uk/sites/default/files/Engagement/Muons%20and%20Special%20Relativity.pdf
> > >
> > > Moving clocks appear to tick more slowly the faster that they are
> > > moving. In their rest frame cosmic ray generated muons have a half life
> > > of about 2.2us which isn't long enough for them to reach the ground even
> > > at nearly the speed of light.
> > >
> > > It is precisely *because* they are moving so quickly that they *DO* last
> > > much longer in our almost stationary observers rest frame on the Earth.
> >
> > You can't even state the problem correctly. Our frame of reference is no more stationary than the muon.
> Our rest frame is stationary with respect the visible universe (give or take our orbital velocity around out galactic centre, and the fact that our galaxy is moving towards the Andromeda galaxy, both at rather small fractions of the speed of light).

Why? That definition is a bit circular. The part of the universe is defined by our rest frame. The muon doesn't care about any of that, does it?

> > This is why it is impossible to define simultaneity under some conditions. In one frame of reference A precedes B, in another frame of reference B precedes A. There is no right answer just as there is no stationary frame of reference.
> Except that the "fixed stars", now called the cosmic microwave background, is just such a stationary frame of reference. Hubble recession means that it isn't exactly stationary, but it does serve the purpose.

The purpose of what? What we can observe, will be defined by our rest frame. Saying our rest frame is defined by what we see is meaningless.

What if we were accelerated to 0.99 c relative to our previous rest frame by passing by a star or black hole? Would that make our rest frame different? Would it change the view of the universe? Would it change the microwave background?

> > Please analyze the muon reaching the ground with the observer moving with the muon rather than on the ground.
> The observer moving with the muon got converted to an extremely warm plasma as soon as it reached the outskirts of the atmosphere.

Yeah, that's what I figured. This stuff is beyond you these days. Sorry about that.

--

Rick C.

-+- Get 1,000 miles of free Supercharging
-+- Tesla referral code - https://ts.la/richard11209

On 08/05/2022 22:39, Joe Gwinn wrote:
> On Sun, 8 May 2022 21:28:52 +0100, Martin Brown
> <'''newspam'''@nonad.co.uk> wrote:
>
>> On 05/05/2022 15:01, Ricky wrote:
>>> On Thursday, May 5, 2022 at 2:12:46 AM UTC-4, bill....@ieee.org
>>> wrote:
>>>> On Thursday, May 5, 2022 at 9:36:25 AM UTC+10, Ricky wrote:
>>>>> On Wednesday, May 4, 2022 at 1:35:57 AM UTC-4,
>>>>> DecadentLinux...@decadence.org wrote:
>>>>>> Mohammad Halai <moha...@ugcloud.ca> wrote in
>>>>>> news:20c1a94c-7c6a-40fc...@googlegroups.com:
>>>>>>> Yesterday, I awoke with the following thought:
>>>>>>>
>>>>>>> Let's imagine Computers A and B have identical specs and are
>>>>>>> both scheduled to run an algorithm that would usually take
>>>>>>> one year at time T, with the A computer being accelerated to
>>>>>>> 0.5c at that time (or anything c). Both are configured to
>>>>>>> send the results to a central computer automatically.
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> From my perspective, would A complete processing first?
>>>>>>>
>>>>>>> Would we be able to pick up A's broadcast?
>>>>>>>
>>>>>>> Would it make a difference if A was traveling in a straight
>>>>>>> line, circling a planet, or even orbiting a star system?
>>>>>>>
>>>>>>> Is it possible to speed up a computer enough that it can
>>>>>>> "compress time" on a machine like the LHC?
>>>>>>>
>>>>>>> I apologize if this question is inappropriate for this group;
>>>>>>> I'm sure someone has asked it, but I'm not sure where to seek
>>>>>>> for the answer—I'm new to all things physics.
>>>>>>>
>>>>>> The speed at which you are moving does not change the speed at
>>>>>> which the computer in your phone does its processing compared
>>>>>> to a stationary phone. The bits toggle at the same rate in
>>>>>> both.
>>>>> Bzzzt! Sorry, wrong answer, even if it is technically correct.
>>>>> You didn't read the problem statement. "the A computer being
>>>>> accelerated to 0.5c" is the part you missed or ignored.
>>>> It isn't even technically correct. Special relativity points out
>>>> that a moving phone is going to be clocked more slowly than a
>>>> stationary phone. Acceleration is indistinguishable from gravity,
>>>> so general relativity requires you to pay attention to the
>>>> acceleration as well, but gravitational red-shift is a different
>>>> thing from Lorentz time-dilation.
>>>
>>> Not sure what you mean about the moving vs. stationary clocks. I
>>> suppose I did not explain adequately. Since constant motion is
>>> purely relative, each clock is *observed* to be slower by the
>>> observer in the other time frame. So clearly, it makes no sense to
>>> talk about one clock actually running slower due to constant motion.
>>> It's just an effect of observation, with no actual change in time
>>> elapsing.
>>
>> There are some cosmic ray muons hitting the ground that would disagree
>> with your perverse and confused interpretation of special relativity.
>>
>> https://ph.qmul.ac.uk/sites/default/files/Engagement/Muons%20and%20Special%20Relativity.pdf
>>
>> Moving clocks appear to tick more slowly the faster that they are
>> moving. In their rest frame cosmic ray generated muons have a half life
>> of about 2.2us which isn't long enough for them to reach the ground even
>> at nearly the speed of light.
>>
>> It is precisely *because* they are moving so quickly that they *DO* last
>> much longer in our almost stationary observers rest frame on the Earth.
>>
>> Their clock time is subject to a gamma factor of about 40x.
>
> I think the problem here is the conflict between two oft-heard
> statements:
>
> 1. Velocity is relative - there is no such thing as a single fixed
> coordinate system for the universe, so there cannot be such a thing a
> as absolute velocity.

It comes back to two fairly simple axioms.

1. The laws of physics are identical for any observer in an inertial
frame of reference (ie in constant linear motion - not accelerating).

2. The speed of light in vacuum is a constant of nature.

Everything else in special relativity follows from that.

> 2. So local time in a moving platform (like a spaceship) passes
> slower and slower the faster the platform is moving.

And that is clearly verified experimentally!

> So in the twin paradox, given that velocity is relative, one ought to
> be able to arbitrarily say that ship 2 is stationary, and ship 1 is
> traveling at 0.9 C, or vice versa. So, how is it that one ages but
> the other doesn't? By symmetry, they cannot differ.
>
> What then breaks the symmetry? The obvious answer is the differences
> in the acceleration histories of the two ships? How?
>
> A clear answer might settle this debate thread.

The thing that matters is that you can only compare times between mutual
events that are defined at fixed coordinates in spacetime. Events where
the twins are colocated however briefly (though preferably in the same
frame of reference) have a well defined spacetime distance between them.

Once they are spatially separated you can choose other reference frames
to alter their spacetime coordinates within certain limits determined by
the light cone of causality. The consequences of an event cannot ever
stray outside the causally connected zone defined by the speed of light.

The only way the twin who travels can ever get back to where he started
is to accelerate in some fashion. Either to go around in a big circle
like the particles in a CERN particle accelerator or for a spaceship by
firing a huge booster rocket when they get a suitable distance away from
the Earth. It will be a long while before we see anything macroscopic
travelling at an appreciable fraction of c.

The experiment has been done a few times with clocks on airplanes and a
stay at home one. Interpretation is complicated by the fact that the
moving clock spends time higher in the Earth's gravitational potential
as well as travelling at ~500kph. The two clocks behaviour exactly
accord with the predictions of special and general relativity.

--
Regards,
Martin Brown

On 09/05/2022 06:56, Ricky wrote:
> On Monday, May 9, 2022 at 1:07:29 AM UTC-4, bill....@ieee.org wrote:
>> On Monday, May 9, 2022 at 1:17:48 PM UTC+10, Ricky wrote:
>>> On Sunday, May 8, 2022 at 9:04:08 PM UTC-4, bill....@ieee.org
>>> wrote:
>>>> On Monday, May 9, 2022 at 7:39:36 AM UTC+10, Joe Gwinn wrote:
>>>>> On Sun, 8 May 2022 21:28:52 +0100, Martin Brown
>>>>> <'''newspam'''@nonad.co.uk> wrote:
>>>>>> On 05/05/2022 15:01, Ricky wrote:

>>>>>>> Not sure what you mean about the moving vs. stationary
>>>>>>> clocks. I suppose I did not explain adequately. Since
>>>>>>> constant motion is purely relative, each clock is
>>>>>>> *observed* to be slower by the observer in the other time
>>>>>>> frame. So clearly, it makes no sense to talk about one
>>>>>>> clock actually running slower due to constant motion.
>>>>>>> It's just an effect of observation, with no actual change
>>>>>>> in time elapsing.
>>>>>>
>>>>>> There are some cosmic ray muons hitting the ground that
>>>>>> would disagree with your perverse and confused
>>>>>> interpretation of special relativity.
>>>>>>
>>>>>> https://ph.qmul.ac.uk/sites/default/files/Engagement/Muons%20and%20Special%20Relativity.pdf
>>>>>>
>>>>>>
>>>>>>
Moving clocks appear to tick more slowly the faster that they are
>>>>>> moving. In their rest frame cosmic ray generated muons have
>>>>>> a half life of about 2.2us which isn't long enough for them
>>>>>> to reach the ground even at nearly the speed of light.
>>>>>>
>>>>>> It is precisely *because* they are moving so quickly that
>>>>>> they *DO* last much longer in our almost stationary
>>>>>> observers rest frame on the Earth.
>>>>>>
>>>>>> Their clock time is subject to a gamma factor of about
>>>>>> 40x.
>>>>> I think the problem here is the conflict between two
>>>>> oft-heard statements:
>>>>>
>>>>> 1. Velocity is relative - there is no such thing as a single
>>>>> fixed coordinate system for the universe, so there cannot be
>>>>> such a thing a as absolute velocity.
>>>>
>>>> Actually there is - the microwave background defines a a zero
>>>> velocity coordinate from which it looks essentially uniform in
>>>> every direction.
>>>
>>> I'm pretty sure that's a fallacy.
>> It isn't.
>
> Oh, but it is.

It has been measured as the cosmic microwave background anisotropy
pretty much ever since the first relatively low resolution COBE probe.
There is a roughly 7% difference in intensity at the survey wavelength
in opposing directions caused by our relative motion with respect to the
original frame of reference of the Big Bang.

It shows up as a ~2.5 sigma detection in the latest data. This isn't a
bad introduction to current state of the art see Figure 2 COBE data.

https://arxiv.org/pdf/1501.04288.pdf

It represents about 3.35mK deviation on a background radiation
temperature of about 2.7K and is about 2.5 sigma detection. The whole
thing is complicated by local galactic plane emissions and foreground
galaxy cluster gas interactions altering the incoming radiation.

The Earth is moving with a very modest velocity relative to the original
Big Bang spacetime coordinate (0,0,0,0). It is mostly dominated by the
motion of our galactic cluster towards the great attractor with minor
corrections for attraction to Andromeda galaxy (collision due in 4.5B
years), suns orbit around our galaxy and Earth's orbit around the sun.

https://en.wikipedia.org/wiki/Great_Attractor

https://en.wikipedia.org/wiki/Andromeda–Milky_Way_collision

>>> Every point in the universe sees the entire rest of the universe
>>> expanding away from that point, including the microwave
>>> background. It should appear the same everywhere in the universe
>>> if you are referring to the extent of the red-shift. What do you
>>> mean exactly by "it looks essentially uniform"? Uniform in what
>>> aspect?
>> As soon as you start moving with respect to the rest of the
>> universe the segment of the microwave background you are moving
>> towards is Doppler shifted to a shorter wavelength, and the segment
>> you are moving away from is Doppler-shifted to a longer
>> wavelength.
>
> So I can measure my speed through the ether? Wow! Too bad Michelson
> and Morley didn't know about this. Who has measured out speed
> through the microwave background? What is our speed relative to the
> universe?
>
> Wow! What if the Universe is itself moving? Maybe the Universe is
> moving at some huge factor of the speed of light? That would be
> trippy!

Go far enough in any direction and there is a good chance that some of
it is already moving away from us faster than the speed of light.

The so called particle horizon that is forever inaccessible to us even
if we set off now at the speed of light. Infinity is *BIG*.
>
>
>>>> It's a proxy for the "fixed stars" which is now the retreating
>>>> galaxies.
>>>>> 2. So local time in a moving platform (like a spaceship)
>>>>> passes slower and slower the faster the platform is moving.
>>>>>
>>>>> So in the twin paradox, given that velocity is relative, one
>>>>> ought to be able to arbitrarily say that ship 2 is
>>>>> stationary, and ship 1 is traveling at 0.9 C, or vice versa.
>>>>> So, how is it that one ages but the other doesn't? By
>>>>> symmetry, they cannot differ.
>>>>>
>>>>> What then breaks the symmetry? The obvious answer is the
>>>>> differences in the acceleration histories of the two ships?
>>>>> How?
>>>>
>>>> Integrating the acceleration gives you velocities.
>>>
>>>>> A clear answer might settle this debate thread.
>>>
>>> That's hard to do. When we consider the moving train analogy,
>>> that typically ignored the method of viewing what is happening on
>>> the other train. I expect this can complicate the matter as
>>> well.

>> If you are in the business of getting and staying confused, you can
>> find a lot of stuff to get confused about.
>
> Yeah, let us know how it works out for you.

He is basically right although it is more of a philosophical point and
it makes no difference whatsoever to the twin paradox. Which isn't a
paradox at all - it just confuses people who don't understand SR.

--
Regards,
Martin Brown