[Iactuallycanthink]

You're asserting that there is a preferred frame of reference. That is in disagreement with modern physics where the consensus is that there is no preferred FoR. How would you back up your position?

If you accept there is no preferred FoR, then there really isn't an issue with something undergoing constant acceleration indefinitely. This is quite literally the worst argument against UA there could be.

Constant acceleration with respect to what ?  You can’t have it both ways.  If an earth slowing its rate of acceleration assumes a preferred FOR, so does an earth that is increasing its rate.

No i did not argue or stipulate any frame of reference ..

I simply used the equations given by FET  for Universal Acceleration.. and showed that at the same time it reaches the maximum speed of  C  it must also  UA must diminish to a limit of  0

that is ALL I DID .. i dont care what frames you pick

[Iactuallycanthink]

I can't hold your hand through understanding Relativity. Clearly you aren't grasping one of the pillars of the theory, which is that in any FoR, an observer in said frame measures the same value for c. Even if that observer is accelerating with respect to another observer. And there is no law that prevents something from undergoing constant acceleration indefinitely. The hypothetical object that is constantly accelerating never exceeds c from its own frame. It is only from outside frames that relativistic effects on its observed velocity would be observed. You need to come to terms with how this all works before you start an argument that is nonsense.

I dont need HAND HOLDING

you  DONT UNDERSTAND RELATIVITY

p1      E        p2

if E is accelerating always toward P2

then P1 sees E moving away at a constant acceleration of  10 m/s^2

but  E cant move faster than C  THIS IS  basic tenant of relativity .. i dont need to argue it it is 

so when the E reaches  the speed of C it is essentially NOT ACCELERATING

no ACCELERATION
 MEANS   no  FORCE DOWN

just moving at C does not create a force down sorrry

the reason  YOU FEEL A FORCE DOWN in an elevator is  BECAUSE THERE IS  gravity  which UNIVERSAL acceleration is supposed to  REPLACE

I HAVE ALSO SHOWN  that  with the equations  from RELATITIVITY THAT THE  FE'S  USE  to prove the validity of UA

that  dv/dt = g (1 - v^2/c^2)^(3/2)

notice that as  v approaches c  that   the  portion under the exponent is  near 0

a number near 0 to any power is a smaller number near 0

is that enough  bloody HAND HOLDING FOR YOU  MR DAVE THE DONKEY

Keep your whining rants in the Angry Ranting forum. See the forum rules if you need further details. Warned.

Also, if you are going to claim to understand relativity, in this case SR, then maybe you should try using the proper equation instead of sticking with classical mechanics. That, and learning how a FoR works, should help keep you from being as proudly ignorant as you are here. It is embarrassing to both you and your fellow RErs.

i was responding to an person who has NO KNOWLEDGE OF  complex let alone simple 

[JSS]

so when the E reaches  the speed of C it is essentially NOT ACCELERATING

The above quote shows you are not grasping the basic theory of relativity.  It's not surprising as it really is a crazy concept to wrap your head around, but the math for Universal Acceleration is quite correct.

But there are tons of great videos and tutorials out there that explain it.  Here is one, but you should look at a bunch until you get the concept. It took me a while before it all clicked, and only a shallow understanding. Don't ask me to quote formulas, they make my head hurt.

https://www.sciencealert.com/watch-the-famous-twin-paradox-of-special-relativity-explained

Nothing about UA breaks any of the rules of relativity, you certainly can accelerate at 1G forever and never reach C.  You just have to remember that time AND space is relative. An outside observer will see you get closer and closer to C but never reach it, and the Earth will experience time dilation and see that observer moving slower and slower. Objects undergoing acceleration change both how they experience moving through time as well as space.

If you want to argue against UA, there are plenty of other options.  Going 99.99999999% of the speed of light means the rest of the universe better be a complete void, because if you hit a single atom at that speed the explosion will vaporize the whole planet instantly. I can't even express how huge the numbers get after experiencing only 6,000 years of 1G acceleration. An outside observer would need to wait 8.843e+1345 years to watch the Earth accelerate for that long.  That's 1,345 zeros.

[Groit]

So according to UA, any outside observers will see the earth travelling near the speed of light and also see our clocks ticking very slowly. Is that correct?

[Groit]

Also, when cosmic rays (protons) collide with the upper atmosphere (or atmolayer), are we travelling into them, or are they travelling towards us?

[JSS]

So according to UA, any outside observers will see the earth travelling near the speed of light and also see our clocks ticking very slowly. Is that correct?

If UA is following the laws of relativity then yes, an outside observer would see earth traveling at near lightspeed if it's been in flight for thousands let alone millions or billions of years.  However with such extreme speed you would likely not be able to make out much at all before it passed with all the light piled up in front, and the light coming back would be so red shifted as to be nearly undetectable.

Also, when cosmic rays (protons) collide with the upper atmosphere (or atmolayer), are we travelling into them, or are they travelling towards us?

It's all relative, pun intended.  If you were riding on one of those particles you would feel like you were standing still as a massive planet came flying at you.  The video I linked gives a good explanation and examples of how two people can both see the other as moving/shorter/slower at the same time. Frankly I wouldn't want to be anywhere near a planet sized object moving at that speed, the radiation would likely sterilize anything even close to it's flight path. Cosmic rays are insanely dangerous if you are in space, and can even kill you (cancer) down here if you get hit by one and are unlucky, and those are just single electrons or protons and not moving anywhere near as fast as a UA earth would be.

The key to understanding relativity is that there is NO SUCH THING as a universal reference frame. There is no "place" that planets or galaxies are put into. You can't ever look at two things and determine which is moving and which is standing still, every reference frame is equally valid. You just pick one and say "For this observation we are using this frame of reference as out viewpoint."  It's hard to do, as we live our whole lives with a single frame of reference, the Earth. It's easy to say this building is still and this car is moving, but what we mean is "That car is moving in reference to the surface of the earth."

[Groit]

Ok, so why do atomic clocks on satellites in orbit tick more slowly than the clocks on the surface of the Earth? what you're saying is that from the satellites frame, the clock on Earth would tick more slowly as well, and they would both cancel out, but that's not what we observe or measure? 

[JSS]

Ok, so why do atomic clocks on satellites in orbit tick more slowly than the clocks on the surface of the Earth? what you're saying is that from the satellites frame, the clock on Earth would tick more slowly as well, and they would both cancel out, but that's not what we observe or measure?

GPS satellites have an added complication.  Their speed makes time go slightly slower, but they are further away from the Earth's gravity well which makes time run slightly faster. 

But we do observe exactly what Einstein predicts, otherwise GPS wouldn't work at all.

Watch the video I posted, it explains how two observers can BOTH see the other as being slower, each measuring the other and both coming up with different results, both being correct from THEIR frame of reference.  Time does not work the way one expects once you start messing around with relativity.  In fact, it's entirely possible for two observers to observe far away events and see them happen in a different order. Who is right?  Again, both... different frames of reference (speed or gravity) will produce different observations. 

It's very weird, but has been proven over and over again in thousands of experiments.  Relativity is one of the most tested theories out there, and has never failed to work exactly as predicted.  So far.  But that's science, when someone finally does break it, we will just modify it and have an even better and more accurate theory.

[Groit]

Time slows down for accelerating frames and this is not what is observed when we measure the life time of Muons passing through the atmosphere. Special relativity only applies in inertial frames, Earth is considered an inertial frame, and we can measure the effects of SR with the Muons which are created from cosmic rays.

This explains it:

There is a type of fundamental particle called a muon, which in many ways resembles an electron. The main differences are the fact that muons are about two hundred times more massive than electrons, and that they decay into their less massive counterparts after a mean lifetime of a few microseconds. Muons can be created in the Earth’s upper atmosphere when high-energy protons from outer space, known as cosmic rays, collide with the atoms they encounter in the upper atmosphere. The muons so generated travel predominantly in a downwards direction, towards the Earth’s surface, at a speed close to the speed of light.

 Experiments show the following result, which at first sight is quite puzzling. At the top of a mountain the number of muons arriving per hour can be measured and recorded. At the bottom of the mountain, say a couple of thousand metres lower down, the number of muons arriving per hour can also be measured and recorded. Since the muons take several microseconds to travel from the top of the mountain to the bottom, a certain fraction of them should have decayed along the way, meaning that less will be detected at the bottom than at the top. In fact, knowing the mean lifetime of a muon (from measurements in the laboratory), one can predict how many muons should be recorded at the bottom of the mountain as a percentage of those recorded at its top.

 And here’s the puzzle: in every case when such an experiment is performed, the number of muons recorded at the bottom of the mountain is far higher than predicted. In other words, far fewer muons have decayed than might be expected. So what’s going on? The crucial fact here is that the muons are travelling close to the speed of light. Einstein’s specialtheory ofrelativity implies that, according to the observer measuring the rate of arrival of the muons, time is passing more slowly for the muons. Consequently, the journey from the top of the mountain to the bottom takes the muons less time than measured by the observer, and more of the muons survive the trip. This result is an example of one of the key concepts of Albert Einstein’s special theory of relativity. It may be paraphrased by the statement ‘moving clocks run slow’.

[JSS]

Time slows down for accelerating frames and this is not what is observed when we measure the life time of Muons passing through the atmosphere. Special relativity only applies in inertial frames, Earth is considered an inertial frame, and we can measure the effects of SR with the Muons which are created from cosmic rays.

This explains it:

There is a type of fundamental particle called a muon, which in many ways resembles an electron. The main differences are the fact that muons are about two hundred times more massive than electrons, and that they decay into their less massive counterparts after a mean lifetime of a few microseconds. Muons can be created in the Earth’s upper atmosphere when high-energy protons from outer space, known as cosmic rays, collide with the atoms they encounter in the upper atmosphere. The muons so generated travel predominantly in a downwards direction, towards the Earth’s surface, at a speed close to the speed of light.

 Experiments show the following result, which at first sight is quite puzzling. At the top of a mountain the number of muons arriving per hour can be measured and recorded. At the bottom of the mountain, say a couple of thousand metres lower down, the number of muons arriving per hour can also be measured and recorded. Since the muons take several microseconds to travel from the top of the mountain to the bottom, a certain fraction of them should have decayed along the way, meaning that less will be detected at the bottom than at the top. In fact, knowing the mean lifetime of a muon (from measurements in the laboratory), one can predict how many muons should be recorded at the bottom of the mountain as a percentage of those recorded at its top.

 And here’s the puzzle: in every case when such an experiment is performed, the number of muons recorded at the bottom of the mountain is far higher than predicted. In other words, far fewer muons have decayed than might be expected. So what’s going on? The crucial fact here is that the muons are travelling close to the speed of light. Einstein’s specialtheory ofrelativity implies that, according to the observer measuring the rate of arrival of the muons, time is passing more slowly for the muons. Consequently, the journey from the top of the mountain to the bottom takes the muons less time than measured by the observer, and more of the muons survive the trip. This result is an example of one of the key concepts of Albert Einstein’s special theory of relativity. It may be paraphrased by the statement ‘moving clocks run slow’.

I'm not sure what you're arguing here. Time slows down to an outside observer looking at a reference frame that is moving faster.  Since all reference frames are relative, both sides will see the other slow down, both sides think they are the ones at rest.

You said this is not what is observed but that's exactly what happens in the quote you provided. From Earth's frame of reference, the Muons are moving close to the speed of light, and time is running slower for them, letting more of them reach the surface than they should.

[pricelesspearl]

Watch the video I posted, it explains how two observers can BOTH see the other as being slower, each measuring the other and both coming up with different results, both being correct from THEIR frame of reference.

 

That is only true if both clocks are in an inertial reference frame, then special relativity applies. If one clock is accelerating and the other isn’t, the accelerating clock will run slower relative to the inertial clock, but both clocks will not run slower relative to one another. In the twin paradox, the traveling twin comes back younger. The traveling twin accelerates, the earth twin does not.

You said this is not what is observed but that's exactly what happens in the quote you provided. From Earth's frame of reference, the Muons are moving close to the speed of light, and time is running slower for them, letting more of them reach the surface than they should

The muons are accelerating, the earth is not.

[Groit]

I'm not sure what you're arguing here. Time slows down to an outside observer looking at a reference frame that is moving faster.  Since all reference frames are relative, both sides will see the other slow down, both sides think they are the ones at rest.

You said this is not what is observed but that's exactly what happens in the quote you provided. From Earth's frame of reference, the Muons are moving close to the speed of light, and time is running slower for them, letting more of them reach the surface than they should.

What I'm trying to say is that the scientists who measure the effects of time dilation for the muons use special relativity in their calculations, and special relativity only works in inertial frames of reference. So that means the Earth's frame of reference is inertial (not accelerating) and the muons frame of reference is inertial (not accelerating, the muons are travelling at a constant speed).

If the Earth was accelerating then the scientists would need to use more rigorous calculations from 'general relativity' for accelerating frames of reference. We know this is not what they're doing, therefore the Earth and the muons must be in 'inertial frames of reference', otherwise SR wouldn't work.

Also, as pricelesspearl pointed out, when one frame is accelerating and the other isn't, time always runs slower for the accelerating frame for both observers. So if the Earth was accelerating like FET suggests, then the scientist would actually measure less muons at the bottom of the mountain because the muons clock would be running faster. 

[Groit]

The muons are accelerating, the earth is not.

The muons are not accelerating, the Earth and the muons are in inertial frames of reference.

[JRowe]

The Earth is not in an inertial frame of reference under RET or the UA FET this thread is about.

[Groit]

The Earth is not in an inertial frame of reference under RET or the UA FET this thread is about.

An inertial frame of reference is a frame of reference in which Newton's first law is very nearly correct, and the Earth is in one of those frames.

So your earthbound personal frame of reference is not, strictly speaking, inertial, nor is any other frame of reference fixed on the Earth. However, the acceleration involved is very small compared with those arising from everyday forces, and its effect is negligible for most everyday observations. Other terrestrial and solar motions involve even smaller accelerations. The Earth’s acceleration due to its orbital motion around the Sun is about an order of magnitude smaller than that due to its axial spinning, whereas the Sun’s acceleration towards the centre of our galaxy is about 3×10^−10 m/s^2. Thus, for most purposes a frame of reference fixed on the Earth provides a very good approximation to an inertial frame. Although a truly inertial frame is something of an idealisation, the non-existence of an ideal inertial frame is not really a problem because there are plenty of frames of reference that are very nearly inertial (i.e. there are plenty of frames of reference in which Newton’s first law is very nearly correct).

[pricelesspearl]

The Earth is not in an inertial frame of reference under RET or the UA FET this thread is about.

In RE, earth is considered inertial as a practical matter.  Any inertial effects on the surface are minor enough not to be considered and the center of the earth would be considered inertial in GR because it is in freefall.

If the earth is accelerating in FET, then by definition, it is not inertial.

[pricelesspearl]

The muons are accelerating, the earth is not.

The muons are not accelerating, the Earth and the muons are in inertial frames of reference.

Yes, you are correct...got my self turned around.

[ImAnEngineerToo]

I’m going to attempt to rectify your broken rhetoric, icanactuallythink...

I think what you are saying is that if the reference frame is to be held at a constant velocity (inertial change of zero), and an acceleration occurs, then the body under some constant or varying acceleration in one direction will not have the same velocity in two different points, as the UA theory seems to indicate?

I believe a FE response, if I understand UA well enough hopefully, is that the reference frame is also accelerating with the earth in time, allowing the earth to net zero inertial energy by accelerating within the accelerating reference frame. Pete, correct me if I‘m wrong.

[pricelesspearl]

I’m going to attempt to rectify your broken rhetoric, icanactuallythink...

I think what you are saying is that if the reference frame is to be held at a constant velocity (inertial change of zero), and an acceleration occurs, then the body under some constant or varying acceleration in one direction will not have the same velocity in two different points, as the UA theory seems to indicate?

I believe a FE response, if I understand UA well enough hopefully, is that the reference frame is also accelerating with the earth in time, allowing the earth to net zero inertial energy by accelerating within the accelerating reference frame. Pete, correct me if I‘m wrong.

All this talk about frame of reference is irrelevant. Yes, in SR you can accelerate ad infinitum without ever reaching c…but it has nothing to do with frame of reference.  Yes, an outside observer in an inertial FoR will see the object slow and contract.   But the object will never reach c whether there is an inertial outside observer or not. It won’t reach c in the accelerating frame of reference either.  In no frame of reference will anybody ever see anything exceed c...at least with current technology.

[Groit]

So, in FET, is the Earth in an inertial frame or a non-inertial frame?