# Absolute Zero v. The Speed of Light

• Atari_Me
In summary: At the other end; [low] temperature does not affect "age" per se, but it may slow down certain time dependent processes.In summary, the conversation discusses the difference in behavior of objects when cooled to near absolute zero versus when accelerated to near the speed of light. The question raised is how to measure the age of objects in these two states and what physical characteristics would be different. The discussion also touches on the impact of temperature on time dependent processes such as radioactive decay and the possibility of measuring aging/decay through methods other than carbon 14 testing. Ultimately, it is concluded that a third object that has been stationary for 100 years would be needed to accurately compare the ages of the two objects in question.
Atari_Me
Hello,

I have a physics question that I am hoping the forum can answer. I have lots of them actually, but I would like to start with the one question and go from there. Ideally the answer to the question should be based upon current accepted physics theory.

The Question:
How do objects behave differently when cooled to near absolute zero versus when accelerated to near the speed of light?

Specifically, if you were to attempt to measure the age of an object that had been cooled to near absolute zero and left in that state for a significant amount of time and an object that had been traveling near the speed of light for a significant amount of time, what physical characteristics would/could you use to discern their age and how would it be different? For the purposes of the question, let's assume 100 years of near 0 and 100 years of travel at 99% the speed of light.

Thx.

You, right now as you read this, are traveling at 99.999999% of the speed of light. Do you feel any different?

Demystifier, berkeman and russ_watters
At the other end; [low] temperature does not affect "age" per se, but it may slow down certain time dependent processes. E.G., the rate of radioactive decay is not temperature dependent, but evaporation is.

Thank you phinds for the response, however the response sidesteps the question somewhat. Various studies have shown that time in GPS satelites traveling around the Earth behaves differently than time tracked on the Earth. It is a small difference, less than a fraction of a second over the course of years, but required programming updates to account for the increased speed relative to objects moving on Earth. If you were to take that same GPS system clock, how would its tracking of time change if cooled to near absolute zero (assuming the components could survive the cooling process). It raises the question of if the objects behave the same, what is the difference between moving near the speed of light and and extreme cooling of objects. Alternatively, if the objects behave differently, can it be ruled out that the GPS clock differences aren't being impacted by the speeds or other unknown forces that relativity does not accout for.

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russ_watters said:
At the other end; [low] temperature does not affect "age" per se, but it may slow down certain time dependent processes. E.G., the rate of radioactive decay is not temperature dependent, but evaporation is.

Hi Russ, based on this, I assume that we are talking about Carbon 14 to determine age. So, what I asssume you are saying is that Carbon 14 testing would not be impacted by a decrease in temp. to near absolute 0. Have any Carbon 14 tests been conducted to determine whether objects moving at accelerated speeds have a measurable difference in Carbon 14 tests with those objects at rest? I assume, Carbon 14 tests cannot be made to be that precise. If not, is there another way to determine aging/decay over time? The critical aspect of the question is two identical objects; one has been frozen near absolute 0 for 100 years, and the other sent into space and accelerated to 99.9% the speed of light for 100 years. You bring them back to Earth and set them on a table, how are they discernably different?

Atari_Me said:
Hi Russ, based on this, I assume that we are talking about Carbon 14 to determine age. So, what I asssume you are saying is that Carbon 14 testing would not be impacted by a decrease in temp. to near absolute 0. Have any Carbon 14 tests been conducted to determine whether objects moving at accelerated speeds have a measurable difference in Carbon 14 tests with those objects at rest? I assume, Carbon 14 tests cannot be made to be that precise. If not, is there another way to determine aging/decay over time? The critical aspect of the question is two identical objects; one has been frozen near absolute 0 for 100 years, and the other sent into space and accelerated to 99.9% the speed of light for 100 years. You bring them back to Earth and set them on a table, how are they discernably different?

You probably need a third object that has been on the table for 100 years.

The answer depends on the objects and how you define or measure their age. In principle, the object that was frozen and the object that remained on the table are 100 years older. Whereas, the object that has been on a high speed space flight is somewhat less than 100 years older.

If the object were a rabbit, say then the rabbit on the table would be long dead and decomposed. The frozen rabbit would be dead but not decomposed and, with a bit of luck, the space rabbit would be very much alive.

russ_watters
PeroK said:
You probably need a third object that has been on the table for 100 years.

The answer depends on the objects and how you define or measure their age. In principle, the object that was frozen and the object that remained on the table are 100 years older. Whereas, the object that has been on a high speed space flight is somewhat less than 100 years older.

If the object were a rabbit, say then the rabbit on the table would be long dead and decomposed. The frozen rabbit would be dead but not decomposed and, with a bit of luck, the space rabbit would be very much alive.

Hi PeroK, the reason why an object on the table was not includes is that it is not relevant to the question. The question revolves around what are the measurable differences between an object that has been subjected to extreme cold versus an object that has been traveling near the speed of light. You note that the object that was frozen is 100 years old and the object that was subjected to high speed space flight would be somewhat less than 100 years old. My question is, how could you prove that? I grant that is what relativity says should be true, but how can you show it? The test itself would take a long time to conduct, but at the end of the test how can we show those objects to be different if they were identical at the start of the test.

What measurements could be taken to show they are now different from each other and what does relativity state should be different about them?

Atari_Me said:
Hi PeroK, the reason why an object on the table was not includes is that it is not relevant to the question. The question revolves around what are the measurable differences between an object that has been subjected to extreme cold versus an object that has been traveling near the speed of light. You note that the object that was frozen is 100 years old and the object that was subjected to high speed space flight would be somewhat less than 100 years old. My question is, how could you prove that? I grant that is what relativity says should be true, but how can you show it? The test itself would take a long time to conduct, but at the end of the test how can we show those objects to be different if they were identical at the start of the test.

What measurements could be taken to show they are now different from each other and what does relativity state should be different about them?

The object on the table is relevant. For example, how do you tell the difference in general between the frozen and unfrozen objects?

There is no general physical test for how old an object is.

Time is measured by a clock. The space experiment could be conducted with an atomic clock, although Hafele and Keating have already done this for airline flights.

What happens to a clock if it gets frozen is more an engineering matter.

Atari_Me said:
Thank you phinds for the response, however the response sidesteps the question somewhat.
@phinds was just pointing out that you have to be careful when discussing speed, because you always need to define what it is relative to. There is no absolute rest for an object, so no single speed. I think you more or less did that, though.

However, it is important to recognize that unlike speed, temperature is not frame dependent.
If you were to take that same GPS system clock, how would its tracking of time change if cooled to near absolute zero (assuming the components could survive the cooling process).
It would not change. So...
It raises the question of if the objects behave the same, what is the difference between moving near the speed of light and and extreme cooling of objects.
There is no relationship.
Atari_Me said:
Hi Russ, based on this, I assume that we are talking about Carbon 14 to determine age.
Not specifically, no. There are lots and lots of different isotopes that decay and any of them can be used as a clock/calendar.
So, what I asssume you are saying is that Carbon 14 testing would not be impacted by a decrease in temp. to near absolute 0. Have any Carbon 14 tests been conducted to determine whether objects moving at accelerated speeds have a measurable difference in Carbon 14 tests with those objects at rest? I assume, Carbon 14 tests cannot be made to be that precise.
Correct; it can't be tested directly with current technology.
If not, is there another way to determine aging/decay over time?
By accepting the theory of Relativity and using it as a basis for calculations.
The critical aspect of the question is two identical objects; one has been frozen near absolute 0 for 100 years, and the other sent into space and accelerated to 99.9% the speed of light for 100 years. You bring them back to Earth and set them on a table, how are they discernably different?
The one that has gone into space is younger, but how they are different will depend on how the object ages. If the two objects are gold bars, they won't look much different. But it is very critical to recognize here that just because an object ages well, that doesn't mean it isn't actually older. It is.
Alternatively, if the objects behave differently, can it be ruled out that the GPS clock differences aren't being impacted by the speeds or other unknown forces that relativity does not accout for.
This goes back to phinds' point. Aging (or any physical proces) *can't* be affected by speed, because an object has an infinite number of differend speeds at the same time. The only viable explantion for what is observed is that the passage of time itself is frame dependent.

This line of questioning has the feel of something we get a lot; people are uncomfortable with Relativity and seek a way to explain it away by converting it into a process-dependent thing. E.G., leave your leftover dinner out of the fridge overnight and it looks older than if you'd have kept it in the fridge. It's not, and that's not what Relativity is. It's a common feeling of discomfort and line of questioning, but it really doesn't go anywhere.

phinds and PeroK
So far the response seem to revolve around radioactive decay as the measuring stick to show change in 'age' over time. This begs the question, what other measuring sticks do we have to show change in the 'age' of an object over time?

I agree that discerning the differences between objects frozen and objects accelerated may dip into engineering a bit, but it is also relativity related as one of the primary principles of relativity is that if you remove reference points, determining whether an object is moving toward you or you are moving toward the object is impossible, or at least irrelevant. This question goes to the heart of the same thing, if you remove the reference point of freezing or moving near the speed of light, how can you discern that an object has been moving near the speed of light when compared to a deeply frozen object.

Going to your comment Russ about the clock would not be impacted by near zero temperatures, are there any studies to show this? The components of the clock would most certainly be impacted. Electricity is impacted by an number of things. What I am trying to sort out here is how you can show that at object moving near the speed of light is being impacted by Einsteinian relativity and not another force, perhaps one unaccounted for.

Atari_Me said:
What I am trying to sort out here is how you can show that at object moving near the speed of light is being impacted by Einsteinian relativity and not another force, perhaps one unaccounted for.
Now you're leaving science behind and wandering off into personal speculation, which is no-no on this forum.

If you don't like the science, well nature just doesn't care. If you study it a bit more you'll come to terms with your dissatisfaction.

russ_watters
In addition, Carbon 14 age testing depends on radioactive decay. As far as I know, radioactive decay rates do not change at low temperatures.

russ_watters
It's a no-no to question theories? Dark matter, anti-matter, spooky action, these are all concepts created to account for physics that we do not entirely understand. Relativity cannot account for everything, that's why String Theory exists. But a basic scientific fact is that one of the theories may be true, but neither has to be. Questioning theories is absolutely necessary for science. Were it not, we would still be living in a world of Phlogistons.

Part of the main point of all this is what is time relative to the 'real' world. We measure time through the change in the state of objects such as movement and decay. If Relativity states that an object on Earth would have an X rate of decay over 100 years and an object which leaves the Earth for 100 years and returns would have a Y rate of decay. If the rate of decay can be nullified through freezing to near absolute temperatures, such that the object that remained on Earth has an near identical rate of decay to the rate for the object that left Earth,what is left to show that freezing is different from acceleration to near the speed of light. I'm not doubting that there is a difference, I'm simply asking how we can show that difference.

Atari_Me said:
It's a no-no to question theories? Dark matter, anti-matter, spooky action, these are all concepts created to account for physics that we do not entirely understand. Relativity cannot account for everything, that's why String Theory exists. But a basic scientific fact is that one of the theories may be true, but neither has to be. Questioning theories is absolutely necessary for science. Were it not, we would still be living in a world of Phlogistons.

Part of the main point of all this is what is time relative to the 'real' world. We measure time through the change in the state of objects such as movement and decay. If Relativity states that an object on Earth would have an X rate of decay over 100 years and an object which leaves the Earth for 100 years and returns would have a Y rate of decay. If the rate of decay can be nullified through freezing to near absolute temperatures, such that the object that remained on Earth has an near identical rate of decay to the rate for the object that left Earth,what is left to show that freezing is different from acceleration to near the speed of light. I'm not doubting that there is a difference, I'm simply asking how we can show that difference.
You continue to misunderstand the science. Objects that travel at relativistic speeds relative to you are not affected in the least. Radioactive rate of decay does not change at all. What you are doing is confusing some non-existent "absolute time" with differential aging. Again, study the science and you'll get rid of your misconceptions.

Atari_Me said:
So far the response seem to revolve around radioactive decay as the measuring stick to show change in 'age' over time. This begs the question, what other measuring sticks do we have to show change in the 'age' of an object over time?

I agree that discerning the differences between objects frozen and objects accelerated may dip into engineering a bit, but it is also relativity related as one of the primary principles of relativity is that if you remove reference points, determining whether an object is moving toward you or you are moving toward the object is impossible, or at least irrelevant. This question goes to the heart of the same thing, if you remove the reference point of freezing or moving near the speed of light, how can you discern that an object has been moving near the speed of light when compared to a deeply frozen object.

Going to your comment Russ about the clock would not be impacted by near zero temperatures, are there any studies to show this? The components of the clock would most certainly be impacted. Electricity is impacted by an number of things. What I am trying to sort out here is how you can show that at object moving near the speed of light is being impacted by Einsteinian relativity and not another force, perhaps one unaccounted for.

You're over 100 years too late to be seriously concerned with the basic principles of relativity. All of the high energy experimental physics, such as that at CERN, is conducted on the basis of special relativity. Time dilation is only one aspect of a theory that governs the energy and momentum of particle collisions, for example.

It would make no sense, for example, to imagine that a high speed proton at CERN is somehow frozen.

Science has moved on since 1905, so no one is going to be interested in wild speculation as an alternative to relativity.

Atari_Me said:
So far the response seem to revolve around radioactive decay as the measuring stick to show change in 'age' over time. This begs the question, what other measuring sticks do we have to show change in the 'age' of an object over time?
Well, no - radioactive decay was chosen because it is not affected by environmental factors like temperature, so it is very consistent. But *any* stable and time dependent process can be used to measure the passage of time, to a certain level of accuracy as long as other environmental factors are controlled for; Tree rings, at-bats, beers consumed, wrinkle depth, denim fading...anything. So that means any radioactive decay can be used, depending on other practical considerations. For example, some medical imaging uses Molybnium 99, which has a half life of 3 days. You could probably age a week-old sample to within an hour of its actual age.

Be careful here with your definitions, though: don't play games with the definitions of "age" and "time". Again; you can change the impact that the passage of time has on an object by altering environmental factors, but you cannot change its *actual* age.
I agree that discerning the differences between objects frozen and objects accelerated may dip into engineering a bit, but it is also relativity related as one of the primary principles of relativity is that if you remove reference points, determining whether an object is moving toward you or you are moving toward the object is impossible, or at least irrelevant. This question goes to the heart of the same thing, if you remove the reference point of freezing or moving near the speed of light, how can you discern that an object has been moving near the speed of light when compared to a deeply frozen object.
No. Again; temperature is not frame dependent. The reason why is simple: the motion of molecules in a substance is random, so it has a specific rest frame. It is *not* the same as the speed of an extended object.
Going to your comment Russ about the clock would not be impacted by near zero temperatures, are there any studies to show this?
Absolutely. Controlling for/predicting/assessing environmental factors, such as temperature, is a critical component of metrology, for measuring anything.
The components of the clock would most certainly be impacted.
As you said earlier; other than physical damage that prevents its operation. If you freeze a mechanical clock and the hands stop moving because of it, that doesn't have anything to do with the actual rate of the passage of time.
What I am trying to sort out here is how you can show that at object moving near the speed of light is being impacted by Einsteinian relativity and not another force, perhaps one unaccounted for.
Again, be careful here: you are again straying into @phind's point of confusing absolute and relative speeds. An object cannot be affected by speed itself because it has an infinite number of speeds at the same time. The only viable explanation for Relativity is that the passage of time is frame dependent, not that it is speed dependent.

This might sound like a semantic issue, but it's really not and confusing the two issues would become a problem if you started discussing General Relativity and gravity. Unlike speed, gravity can affect physical processes. A puendulum clock would behave differently on the moon than on Earth in addition to the actual time dilation that is occurring. So you need to understand the difference and be able to account for both when they are both present and recognize when only one is present.

Also, I feel I need to remind you that PF's rules prohibit discussion of non-mainstream ideas. It is fine to ask why Relativity works or how we know, but it is not ok to start with a premise of rejecting it and actively looking for an alternative. You're getting close to that line.

So, your argument is that we shouldn't question accepted science. Galileo would be disappointed.

Atari_Me said:
So, your argument is that we shouldn't question accepted science. Galileo would be disappointed.
No, I don't think he would. You are NOT questioning accepted science, you are denying it because you don't understand it.

russ_watters
Atari_Me said:
So, your argument is that we shouldn't question accepted science. Galileo would be disappointed.
It is a more practical point than that. Permitting discussion and promotion of all sorts of ideas, including those that are dead on arrival will kill a forum dead. If you'd ever experienced sci.physics, you could have seen that in action. But arguing about the rules is off topic, so I'll leave it at that.

russ_watters
Atari_Me said:
So, your argument is that we shouldn't question accepted science. Galileo would be disappointed.

Let's say you went to a medical conference and you proposed that the brain, not the heart, pumps blood round the body. What would they say?

The question is what science do you want to review and why.

Time moves on. The debates on relativity took place over 100 years ago. And the great debates on QM took place in the 20s and 30s. These are the scientific debates of the past.

Special Relativity may seem new and radical to you but it is a solid cornerstone of modem physics. No one is going to reopen a hundred year old debate without a significant new discovery. And, one student trying to learn the basics of relativity and doubting it does not and cannot be considered significant new evidence.

russ_watters
I'm not trying to pose anything about alternative theories of science. LOL. It is simply a question about what are the measuring sticks that show differences in behavior of objects moving near the speed of light relative to an object at rest on Earth and how that differs from an object being frozen near absolute zero. It's not exactly a mainstream topic for discussion around the water cooler, therefore it seems the appropriate place to pose the questions. I am looking for the theoretic difference and the provable differences. Certain measuring sticks can be duplicated, others hopefully cannot, I am trying to sort out which measuring sticks cannot be duplicated that would allow someone to determine the difference between the objects.

Atari_Me said:
It's a no-no to question theories?
It is on PF, yes. More broadly, it isn't going to do you any good to find another forum more open to such things because even if there is an open question in science (and this isn't one), a layperson has essentially zero chance of solving it. You are wasting your time.
Part of the main point of all this is what is time relative to the 'real' world. We measure time through the change in the state of objects such as movement and decay. If Relativity states that an object on Earth would have an X rate of decay over 100 years and an object which leaves the Earth for 100 years and returns would have a Y rate of decay. If the rate of decay can be nullified through freezing to near absolute temperatures, such that the object that remained on Earth has an near identical rate of decay to the rate for the object that left Earth,what is left to show that freezing is different from acceleration to near the speed of light.
Even if you weren't now citing something factually wrong to support your argument...

Is closing your eyes functionally equivalent to the sun shutting off? You cannot change reality or the laws of physics by ignoring them. A pot of water boils faster if I turn up the heat. Deciding to ignore the laws of physics and pretending time spend up instead doesn't work. It's a wrong way to think.

Atari_Me said:
Hello,

The Question:
How do objects behave differently when cooled to near absolute zero versus when accelerated to near the speed of light?

According to the perspective of a muon, YOU are traveling near the speed of light. Have you "behaved differently" lately?

Zz.

PeroK said:
Let's say you went to a medical conference and you proposed that the brain, not the heart, pumps blood round the body. What would they say?

The question is what science do you want to review and why.

Time moves on. The debates on relativity took place over 100 years ago. And the great debates on QM took place in the 20s and 30s. These are the scientific debates of the past.

Special Relativity may seem new and radical to you but it is a solid cornerstone of modem physics. No one is going to reopen a hundred year old debate without a significant new discovery. And, one student trying to learn the basics of relativity and doubting it does not and cannot be considered significant new evidence.

I would argue that we invite debates about Relativity every day through 1) the development and advancement of String Theory, and 2) the fact that we call it the Theory of Relativity and not the Law of Relativity. Regardless, I am not trying to challenge Relativity, I am simply trying to understand better how Relativity accounts for certain action.

Atari_Me said:
...I am simply trying to understand better how Relativity accounts for certain action.
But you persist in believing that relativity does something that it does not do. You will NEVER understand how relativity does something when it doesn't DO that something. Again, study the science rather than argue about it.

Atari_Me said:
I would argue that we invite debates about Relativity every day through 1) the development and advancement of String Theory, and 2) the fact that we call it the Theory of Relativity and not the Law of Relativity. Regardless, I am not trying to challenge Relativity, I am simply trying to understand better how Relativity accounts for certain action.

The words "theory", "law", "model", etc. are interchangeable in physics. If you are that hung up on the English words we use, then you have not understood the physics.

Zz.

ZapperZ said:
According to the perspective of a muon, YOU are traveling near the speed of light. Have you "behaved differently" lately?

Zz.
Exactly what I told him in the very first response in this thread. I don't think he gets it.

Atari_Me said:
The question revolves around what are the measurable differences between an object that has been subjected to extreme cold versus an object that has been traveling near the speed of light.
Do you realize that the key portion of atomic clocks are refrigerated? Not because it changes the rate at which time is measured to pass but because it increases the accuracy of the measurements.

russ_watters
Atari_Me said:
My question is, how could you prove that? I grant that is what relativity says should be true, but how can you show it?

With all due respect, this experiment is noted in almost every book on relativity:
https://web.mit.edu/8.13/8.13c/references-fall/muons/frisch-smith-1963.pdf
Perhaps some preliminary independent research by the OP would be useful.

phinds said:
Exactly what I told him in the very first response in this thread. I don't think he gets it.

I was trying to repeat it just so he/she realizes that he/she does not understand the very basic concept that underlies Special Relativity, hoping that it will be an impetus for him/her to want to actually learn it more carefully than simply having an endless stream-of-thought conversation on here.

Zz.

russ_watters and phinds
russ_watters said:
Is closing your eyes functionally equivalent to the sun shutting off? You cannot change reality or the laws of physics by ignoring them. A pot of water boils faster if I turn up the heat. Deciding to ignore the laws of physics and pretending time spend up instead doesn't work. It's a wrong way to think.

What are you talking about? I'm not trying to change anything nor am I ignoring any laws of physics. If you lack the engineering/chemistry backgroud to describe how absolute 0 impacts objects, ok, that aspect is a question for another forum. Let's focus on Relativity, and I will keep it simple. If an object were to leave Earth for 100 years and accelerate to 99% the speed of light and then returned to Earth at the end of the 100 years, and an identical object remained on Earth. Let's use a block of wood as an example. And the block of wood was maintained in a sealed vacuum chamber for the duration of the 100 years, I assume that various types of radioactive decay would be the measuring stick to show the age difference between the objects? Would there be any other measuring stick that could show change between the two objects?

Atari_Me said:
What are you talking about? I'm not trying to change anything nor am I ignoring any laws of physics. If you lack the engineering/chemistry backgroud to describe how absolute 0 impacts objects, ok, that aspect is a question for another forum. Let's focus on Relativity, and I will keep it simple. If an object were to leave Earth for 100 years and accelerate to 99% the speed of light and then returned to Earth at the end of the 100 years, and an identical object remained on Earth. Let's use a block of wood as an example. And the block of wood was maintained in a sealed vacuum chamber for the duration of the 100 years, I assume that various types of radioactive decay would be the measuring stick to show the age difference between the objects? Would there be any other measuring stick that could show change between the two objects?
What's your point? It is both an empirical fact and according to theory that the traveling piece of wood would have aged less. So what? It doesn't matter what you use to detect the differential aging, it's there and that's a fact. The rate of radioactive decay, like the rate of all biological processes, for the traveling piece just ticks along at 1 second per second, just as you are doing right now even though you are traveling at near light speed.

russ_watters
phinds said:
But you persist in believing that relativity does something that it does not do. You will NEVER understand how relativity does something when it doesn't DO that something. Again, study the science rather than argue about it.

Your first response brought up the fact that we are already traveling extremely fast. That's all. Do you often start your experiments with items that do not have an impact on the results? I didn't include the speed of the Earth, the Milky Way, the Universe, because they had no bearing on the question posed. You understood the intent of the question at the outset and chose provide a snarky response.

Atari_Me said:
Your first response brought up the fact that we are already traveling extremely fast. That's all. Do you often start your experiments with items that do not have an impact on the results? I didn't include the speed of the Earth, the Milky Way, the Universe, because they had no bearing on the question posed. You understood the intent of the question at the outset and chose provide a snarky response.
And yet you chose to include the speed of an object. Which is equally irrelevant. Speed is not an invariant property of an object.

Atari_Me said:
Your first response brought up the fact that we are already traveling extremely fast. That's all. Do you often start your experiments with items that do not have an impact on the results? I didn't include the speed of the Earth, the Milky Way, the Universe, because they had no bearing on the question posed. You understood the intent of the question at the outset and chose provide a snarky response.
My response was intended to point out to you the error in your thought process, exactly as was zapper in post #23. You continue to seem more interested in arguing about it than in learning the science.

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