Jump to content

speed of light hypothetical

Featured Replies

Oh its all cool.

 

So back to the original Q, so, due to blue shift the radio would send out high pitched, fast sounds?

that sounds about right. Alastair Reynolds had a similar scenario to this in his science fiction novel Revelation Space. In the novel (fiction, of course) radio transmissions were coming being heard in "chipmunk" style when they ship was travelling near the speed of light.

that sounds about right. Alastair Reynolds had a similar scenario to this in his science fiction novel Revelation Space. In the novel (fiction, of course) radio transmissions were coming being heard in "chipmunk" style when they ship was travelling near the speed of light.

 

One would hope that you would make the same compensation for the demodulation as for the frequency of the transmission.

In the last 10 years or so, and even longer ago in alot of cases, the concept of relativistic mass has been removed. It is more common to consider just one mass, which is identical to rest mass, and have the relativistic effects contained within energy and momentum transformations. This use of mass is the one that is prefered on this site, as cameron marical has probably read quite a few posts here it is likely that he would be more familiar with using the the one mass, as opposed to specifying rest mass.

Proton presented some cogent and well-researched arguments here why we should decide to talk different. Why we should talk like he does, and somebody named Koks does, instead of the way we are used to. Proton and Koks argue that it would be more "convenient." And they cite wellknown precedents such as Rindler.

 

Semantic crusades can be interesting in their own right but they are not physics. Not science of any sort, actually. Since we don't have a special place for preaching by semantic missionaries I think the best venue is Pseudoscience forum.

 

I've moved these arguments to a special Semantic Reform thread in Pseudo.

http://www.scienceforums.net/forum/showthread.php?p=500597#post500597

We can discuss the issue there without disrupting regular science forums.

We had essentially the same discussion with Pete a while back. He was campaigning for the same mass terminology. Using words different, it is argued, would be more "convenient". Anyone who feels strongly about this kind of convenience please join our discussion down in Pseudo.

 

I'm fine with whatever folks decide as long as any change is coherent consistent and deliberate.

Edited by Martin
Consecutive posts merged.

  • 2 weeks later...

gamma is approx 10

doppler is approx. 20

he hears 2 yr + 1 day

in approx 36 days

With Respect to the q that this thread started off with : -

 

Aren't there two cases of time dilation we have to consider? Assuming the spacecraft in which the person moves about is closed,(?) then due to the large forward acceleration, this guy is essentially pushed against the walls behind. So, he is at rest in a pseudo gravitational field. So as an observer he does not obey the principle of equivalence. Thus, there is a sense of time dilation for him.

 

As the velocity of the craft is close to that of light, so is this guy's. But with respect to the radio, he is at rest as it is also in the craft and with the same velocity as this guy. So there wouldn't be a sense of time dilation in this respect, would it?

With Respect to the q that this thread started off with : -

 

Aren't there two cases of time dilation we have to consider? Assuming the spacecraft in which the person moves about is closed,(?) then due to the large forward acceleration, this guy is essentially pushed against the walls behind. So, he is at rest in a pseudo gravitational field. So as an observer he does not obey the principle of equivalence. Thus, there is a sense of time dilation for him.

 

Describing the effects of an accelerated frame can be tricky. To someone not accelerating with him, there is no additional time dilation other than that due his velocity.

For the person accelerating, clocks in the direction he is accelerating run fast and clocks in the opposite direction run slow. The farther away the clock is from him, the faster or slower it will run. This includes clocks that share his acceleration. A clock in the tail of the ship will run slower than one in the nose.

i understand the time dilation part due to velocity. but how is it the clock acceleration direction with respect to him determining the rate at which the time moves? i suppose it is due to the gravitational redshift or blueshift of light is his region depending upon whether it is moving away or towards him.

Archived

This topic is now archived and is closed to further replies.

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.

Configure browser push notifications

Chrome (Android)
  1. Tap the lock icon next to the address bar.
  2. Tap Permissions → Notifications.
  3. Adjust your preference.
Chrome (Desktop)
  1. Click the padlock icon in the address bar.
  2. Select Site settings.
  3. Find Notifications and adjust your preference.