On 08/05/2022 22:41, Lasse Langwadt Christensen wrote:
> 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
>
Trouble is, he's worked for say a few months and comes back to find his
mortgage is a few years in arrears. Mind you with enough dilation, he
could inherit plenty from his children.

--
Cheers
Clive

On 09/05/2022 09:48, Martin Brown wrote:

<snip>
>
> 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.
>

What happens to a clock in orbit, ie in freefall?

--
Cheers
Clive

On Mon, 9 May 2022 09:48:09 +0100, Martin Brown
<'''newspam'''@nonad.co.uk> wrote:

>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.

Yes.

>> 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!

Yes. Always a good thing.

>> 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.

True, but all this is hard for non-physicists in the audience to
follow or really understand.

>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.

Yes.

The problem is that the above assumes too much background.

Now, Einstein did not start with all that math, he started with a
collection of gedanken experiments. I suspect that Einstein has a few
relevant examples, which would be very useful if stated (or linked)
here.

Joe Gwinn

On 9/5/22 11:19 pm, Clive Arthur wrote:
> On 09/05/2022 09:48, Martin Brown wrote:
>
> <snip>
>>
>> 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.
>
> What happens to a clock in orbit, ie in freefall?

The pendulum stops swinging :)

On Tuesday, May 3, 2022 at 8:55:28 p.m. UTC-4, 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?
>
> 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.

Ive found an answer off a different forum here it is if your interested.

1) No, because it's actually going slower from your perspective. In special relativity, "the fastest wristwatch is always your own".

2) Yes, but remember that it's farther away from us now, so it will take some time to get to us (if it was travelling at 0.5c it will take 50% longer to get to us).

3) Mostly in that as an observer the redshift effect would be different.

4) It would be feasible to accelerate to dialate time, but that wouldn't be useful.

Since you only mention acceleration to 0.5c, we'll assume we're dealing with special relativity alone. In this case, your accelerating computer 'loses time' -- its clock moves slower. Computers ultimately work on clock cycles.. Thus it is fair to say that, as its clocking is ticking slower -- from your point of view -- the computer on your desk will finish first.

As its clock is ticking slower, it'll take longer to perform the same calculation...from your point of view. The Lorentz transformation gives the ratio by which the travelling clock will slow:

γ−1=(1−v2/c2)−−−−−−−−−√=(1−0.52−−−−−−−√)≈0.86, (or γ≈1.154)

Second question meaningless given the above; if it landed back on your desk after a year's round trip, your desktop machine would be finished, it wouldn't (from the above, if you start 1 Jan one year, start looking for an answer midway through Feb the year after).

Here it gets interesting. If it was orbiting a planet, gravitation comes into play, and with it general relativity. For example, Wikipedia says GPS satellites lose ~7ns/day due to special relativity, but gain ~45ns a day due to general relativity. So instead of cruising at 0.5c, you might want to fling your computer off to 'park' far away from really big planets.
Possible? Yes. Feasible? Depends on the length of your calculation, the cost of building the equipment needed to achieve it, and the benefits of the -- possibly marginal -- decrease in calculation time. I suppose one might conceive of some futuristic 'space station supercomputer receiving station' in orbit around a black hole.

You're thinking about gravitational time dilation.

Time machines do exists. If you go in a space ship and travel around the supermassive blackhole in the center of Milky Way, close enough to not fall in it, and then come back to Earth, you just traveled to the future (relative to the space further from you). So in that thinking line, if you want to make a computer run faster by gravitational time dilation, you must be living in an environment of extremely high gravity and put your computer outside this environment, where time runs faster relative to you. A computer orbiting the Earth will be faster than a computer here, but just by a few nanoseconds.

Would we be able to recieve the broadcast from this computer? Yes, the same way we are able to receive pictures sent from Jupiter by Voyager 1 and 2, we would need to count the interference in the transmission but nothing more than stretching/shrinking waves.

On 09/05/2022 14:19, Clive Arthur wrote:
> On 09/05/2022 09:48, Martin Brown wrote:
>
> <snip>
>>
>> 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.
>>
>
> What happens to a clock in orbit, ie in freefall?

It is further up the gravitational potential than one on the ground and
in addition it is orbiting at a fair old clip. Both corrections have to
be applied to the local clocks in Earth orbit or else GPS wouldn't work.

This is NIST's chapter and verse on the design of GPS receivers and
relevant relativistic corrections that are normally applied (and also
the various really tiny ones that are not).

<https://www.govinfo.gov/content/pkg/GOVPUB-C13-83ec647d39931e27e1a786845bb825c2/pdf/GOVPUB-C13-83ec647d39931e27e1a786845bb825c2.pdf>

It goes into some detail on common engineering misconceptions (which
ISTR led to the first few satellites going up with a defeat switch on
their oscillator correction circuitry because enough electronics
engineers didn't believe in relativity.

Gravitational redshift was the last of the notable GR predictions to be
experimentally verified in the lab using Mossbauer resonance in the
Pound-Rebka experiment:

https://en.wikipedia.org/wiki/Pound–Rebka_experiment

--
Regards,
Martin Brown

On Sunday, May 8, 2022 at 6:04:08 PM UTC-7, bill....@ieee.org wrote:
> On Monday, May 9, 2022 at 7:39:36 AM UTC+10, Joe Gwinn wrote:

> > 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.

> It's a proxy for the "fixed stars" which is now the retreating galaxies.

Alas, that's LOCAL coordinate only; the 'retreating galaxies' all have their
own 'uniform in every direction' situation, affirming that their motion is the
zero velocity coordinate... because the background seen from each point and
velocity has different horizon and redshift..

All locations in an expanding universe are the center...

On Monday, May 9, 2022 at 1:20:49 AM UTC-7, bill....@ieee.org wrote:
> On Monday, May 9, 2022 at 4:07:14 PM UTC+10, Ricky wrote:
> > On Monday, May 9, 2022 at 1:19:02 AM UTC-4, bill....@ieee.org wrote:

> > > 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?
> Clearly it does, otherwise it would decay a lot faster.

It's clear, from the rest frame of the muon, that the depth of atmosphere
it traverses at its relative speed is less, therefore the time elapsed shorter, than
the Earthbound observer calculates.
The muon and observer agree on relative speed, but neither on distance nor time.

> > > > 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.

On 11/05/2022 19:38, whit3rd wrote:
> On Sunday, May 8, 2022 at 6:04:08 PM UTC-7, bill....@ieee.org wrote:
>> On Monday, May 9, 2022 at 7:39:36 AM UTC+10, Joe Gwinn wrote:
>
>>> 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.
>
>> It's a proxy for the "fixed stars" which is now the retreating galaxies.
>
> Alas, that's LOCAL coordinate only; the 'retreating galaxies' all have their
> own 'uniform in every direction' situation, affirming that their motion is the
> zero velocity coordinate... because the background seen from each point and
> velocity has different horizon and redshift..
>
> All locations in an expanding universe are the center...

All locations are at the centre of an observable universe around them
but that doesn't prevent the platform you happen to be on having some
relative motion wrt that static central position that can be determined
by observing the surface of last scattering of the microwave radiation.

The dipole moment of the microwave background is not zero. We are headed
towards the Great Attractor in Leo at quite a speed ~1000km/s.

We really are moving in a measurable way wrt to the original baseline
coordinate frame of the Big Bang. The data are noisy but there is a ~3mK
dipole moment in addition the the uniform 3.7K afterglow.

This is a reasonably nice introduction to the data from the COBE era
from SciAm in 1998.

https://www.scientificamerican.com/article/how-fast-is-the-earth-mov/

--
Regards,
Martin Brown

On Thu, 12 May 2022 08:30:37 +0100, Martin Brown
<'''newspam'''@nonad.co.uk> wrote:

>On 11/05/2022 19:38, whit3rd wrote:
>> On Sunday, May 8, 2022 at 6:04:08 PM UTC-7, bill....@ieee.org wrote:
>>> On Monday, May 9, 2022 at 7:39:36 AM UTC+10, Joe Gwinn wrote:
>>
>>>> 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.
>>
>>> It's a proxy for the "fixed stars" which is now the retreating galaxies.
>>
>> Alas, that's LOCAL coordinate only; the 'retreating galaxies' all have their
>> own 'uniform in every direction' situation, affirming that their motion is the
>> zero velocity coordinate... because the background seen from each point and
>> velocity has different horizon and redshift..
>>
>> All locations in an expanding universe are the center...
>
>All locations are at the centre of an observable universe around them
>but that doesn't prevent the platform you happen to be on having some
>relative motion wrt that static central position that can be determined
>by observing the surface of last scattering of the microwave radiation.
>
>The dipole moment of the microwave background is not zero. We are headed
>towards the Great Attractor in Leo at quite a speed ~1000km/s.
>
>We really are moving in a measurable way wrt to the original baseline
>coordinate frame of the Big Bang. The data are noisy but there is a ~3mK
>dipole moment in addition the the uniform 3.7K afterglow.
>
>This is a reasonably nice introduction to the data from the COBE era
>from SciAm in 1998.
>
><https://www.scientificamerican.com/article/how-fast-is-the-earth-mov/>

Given that the microwave background was discovered in 1964, call it
forty years after Relativity (Special and General) were developed, I'd
hazard that Relativity does not depend in any way on that background.

Joe Gwinn

On Monday, May 9, 2022 at 4:14:08 PM UTC-4, Joe Gwinn wrote:
> On Mon, 9 May 2022 09:48:09 +0100, Martin Brown
> <'''newspam'''@nonad.co.uk> wrote:
>
> >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悠'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.
> Yes.
> >> 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!
> Yes. Always a good thing.

Please explain to me how you determine speed. Motion without acceleration appears to be "at rest" for the observer in motion. So the time affect is only a relative one where each observer sees the other as slowing down. That was the point of the theory, that the passage of time is relative to the observer.

Apply this theory to a rapidly spinning object. Does time pass differently for the different radius parts? So the center sees the outer parts "ticking" more slowly, such as radioactive decay? If you spin a radioactive object, does this reduce the emitted radiation?

--

Rick C.

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

On 2022-05-15 17:41, Ricky wrote:
> On Monday, May 9, 2022 at 4:14:08 PM UTC-4, Joe Gwinn wrote:
>> On Mon, 9 May 2022 09:48:09 +0100, Martin Brown
>> <'''newspam'''@nonad.co.uk> wrote:
>>
>>> 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悠'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.
>> Yes.
>>>> 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!
>> Yes. Always a good thing.
>
> Please explain to me how you determine speed. Motion without
> acceleration appears to be "at rest" for the observer in motion. So
> the time affect is only a relative one where each observer sees the
> other as slowing down. That was the point of the theory, that the
> passage of time is relative to the observer.
>
> Apply this theory to a rapidly spinning object. Does time pass
> differently for the different radius parts? So the center sees the
> outer parts "ticking" more slowly, such as radioactive decay? If you
> spin a radioactive object, does this reduce the emitted radiation?
>

It certainly does, or this muon collider project that people work
on at CERN would make no sense,

Jeroen Belleman