Universal Concept of Time (Is the Big Bang wrong?)

[lucien216]

If the Universe started approximately 13.75 billion years ago as theorized by the 'Big Bang' and TIME itself only came into existence at the moment of the Big Bang, then surely this must be 'Universal Time'.

Yet Einstein and special relativity shows us that TIME is relative. There is no such thing as universal TIME. This has been experimentally proven.  

So then how could TIME only have come into existence with the Big Bang, as accepted by many supporters of the Big Bang.

If TIME only came into existence with the Big Bang then that time would be universal. The universe would be 13.75 billion years old for us. And if there are aliens living in another galaxy the universe would have to be 13.75 billion years old for them as well. That Time would not be relative to either of us because the universe would have come into existence at the same moment for everyone in the universe.

We would now have an entity that has been missing from physics - Universal Time. A concept of TIME that is not relative and cannot be relative because the same universe could not come into existence at different points in TIME for beings living in separate galaxies, if TIME itself only came into existence with the Big Bang. If that is the case then the universe is only 13.75 billion years old, relative to us here on earth but could be any age.

Thoughts?   

[John Cuthber]

"If the Universe started approximately 13.75 billion years ago as theorized by the 'Big Bang' and TIME itself only came into existence at the moment of the Big Bang, then surely this must be 'Universal Time'."

No.

[lucien216]

But do you agree that if TIME itself only came into existence at the moment of the Big Bang, that time must be the same for everyone inside the universe? You can call that 'TIME' whatever you like. It must be universal.

The universe cannot come into existence relative to us (at different points in TIME), if we are in different galaxies for example, because TIME itself never existed before the Big Bang. So before this we had no different points in TIME. Time did not exist (according to Big Bang). So if TIME only came into existence at the point of the Big Bang, that TIME must be 'THE SAME' to everyone inside the universe. It must be UNIVERSAL and not relative.

You say "NO", please elaborate. Explain how that TIME can be different for beings living in two separate galaxies for example.

How can the universe come into existence at two different points in TIME, if TIME itself never existed before the Big Bang? How can that 'TIME' be relative. It must be universal. Or the Big Bang must be wrong.  

Thanks for taking the time to ponder this.

Edited January 29, 2020 by lucien216

[Strange]

1 hour ago, lucien216 said:

If the Universe started approximately 13.75 billion years ago as theorized by the 'Big Bang' and TIME itself only came into existence at the moment of the Big Bang, then surely this must be 'Universal Time'.

No. That is not what universal time means. Universal (or absolute) time would mean that all observers would agree about the amount of time that has elapsed sine the big bang. Which they know they wouldn't: it would depend on relative motion, amount of gravitational potential they have experienced, etc.

Also, there is no evidence the universe "started" and valid theories that describe that. So the question is moot, really.

1 hour ago, lucien216 said:

Yet Einstein and special relativity shows us that TIME is relative. There is no such thing as universal TIME. This has been experimentally proven.  

So then how could TIME only have come into existence with the Big Bang, as accepted by many supporters of the Big Bang.

You can't use the theory of relativity to discredit the big bang model because it is based on relativity.

1 hour ago, lucien216 said:

If TIME only came into existence with the Big Bang then that time would be universal.

No. Because different observers experience time differently. 

1 hour ago, lucien216 said:

We would now have an entity that has been missing from physics - Universal Time. A concept of TIME that is not relative and cannot be relative

That would be going back to a model of time that was shown to be wrong by the evidence. What is the point of that?

8 minutes ago, lucien216 said:

But do you agree that if TIME itself only came into existence at the moment of the Big Bang, that time must be the same for everyone inside the universe?

No. For the reasons given above.

9 minutes ago, lucien216 said:

How can the universe come into existence at two different points in TIME

It is the same event, but different amounts of time have elapsed since then as measured by different observers. 

[lucien216]

"It is the same event, but different amounts of time have elapsed since then as measured by different observers. "

Hhhhmm. This is what I wanted to hear. So you saying that the universe could be, say 30 billion years old, for some observers? So the age of the universe is only relative to us then?

P.S. I am not really claiming that there is a "UNIVERSAL TIME" or 'ABSOLUTE TIME', I think there is in fact no absolute time and the universe could be eternal, but only 13.75 billion years old relative to us.  

[Strange]

18 minutes ago, lucien216 said:

"It is the same event, but different amounts of time have elapsed since then as measured by different observers. "

Hhhhmm. This is what I wanted to hear. So you saying that the universe could be, say 30 billion years old, for some observers? So the age of the universe is only relative to us then?  

Yes, in principle.

In fact, our view of the universe is pretty average so it would be hard for any observer to have seen a significantly greater age for the universe than us. But if someone had been in the closest possible orbit around a black hole ever since the earliest black holes were formed then they would see the universe as being only about 8 billion years old (I think - rough bit of mental calculation based on time dilation at the photon sphere).

In reality, any differences actually observed would be much, much smaller than the errors in our estimate of the age. So it is not a practical problem.

[studiot]

57 minutes ago, lucien216 said:

Hhhhmm. This is what I wanted to hear. So you saying that the universe could be, say 30 billion years old, for some observers? So the age of the universe is only relative to us then?

It is more subtle than this.

The 'Universe' for such an observer would be quite different from the 'Universe' we can see.

In fact any observer would see different parts of the universe form any other observer.
We can only see so far and can only infer what is beyond that.
The point is that what we can see at the edge of our visible range is not so very different from what we can see close up.
So we can only asssume there is more similer 'Universe' beyond the range of our vision because it were very different it would affect the conditions at the edge of what we can see and cause that to appear different.

We do not know of any observer (star etc) going at sufficient relative speed to us to observe 30 billion years.

[lucien216]

Thanks. I am trying to wrap by brain around this in practical terms, from the point of view of two separate observers.

So let's say this thing we call 'TIME' only comes into existence at the point of creation.

We both agree that we are viewing the same event. You say that thing we call TIME, that only came into existence at the Big Bang, can be different for the two of us - RELATIVE TO US.

For me the event could have happened 15 billion years ago and for you only 13.75 billion years ago. I'm using smaller differences based on replies. But assume any difference, even slight.

If we are on different galaxies, let's say you are on earth, I'm in a different galaxy on a different planet.

What does 13.75 billion years even mean to me? I would have my own units of time based on my planets rotation, etc……If I never knew about earth I would have no idea of your concept of TIME.

I can only compare TIME relative to you based on your measurement of time. Right?

Maybe what I call 15 billion years on my planet could be exactly 13.75 years on your planet. Or maybe what I call 1 billion years is only a million years to you. I can only compare TIME relative to someone else.   

So now the concept of 'TIME' becomes something based on you. Time is not 'external'. Time is what you experience and can only be different when compared to someone else. That's logical right? 

Let me give you a better example. Say I build a time machine and I travel forward in time by a 100 years, but during the trip I lose my memory. How will I know that I have traveled forward in time? I won't know it unless I have some point to compare it to. I will simply be in the present, not in the future.   

Now let's go back to the Big bang. We are on different planets. We both observe the same event - The Big Bang.

If we never ever meet each other to compare experiences. Time for each of us will be whatever we say it is. I can say the universe is 15 billion years old based on what I call a year. And you on earth can say the universe is 13.75 billion earth years old based on earth time. 

If we do meet, or contact each other somehow, and want to compare our notes on the age of the universe. One of us will have to convert their units of TIME to achieve anything.

If we do this. I can only conclude that my 15 billion years is exactly equal to your 13.75 billion years. Because TIME is only what each one of us says it is.

You could of course use my measurements and agree that the universe is in fact 15 billion Spagoolars old (that’s what we call a year on my planet).

In either case we are using the same measure of TIME. A UNIVERSAL notion of time. If TIME indeed has a creation point at the moment of the Big Bang. 

Lol. I am getting lost in all of this. But thanks for taking the time to engage. I love this topic.

I can't help but feel there is something very important here.  

If you get into a spaceship and travel at twice the speed of time. Or close to a black hole as per your example. How will you know that you are experiencing TIME different to me? You can only know if you compare it to me and convert your units of time to mine.

If you come back to earth from your trip to the event horizon and find that I have aged 60 years and you have only aged by 6 years. Then your 60 years must be equal to my 6 years. Right? If its equal it must be the same. Right?  

This only matters if we have a "start point" or "big bang", lets say you left for the event horizon when we were both 20 years old. That's our reference point. If you have no reference point, you could go to the edge of a black hole and come back and never know that you traveled faster or slower because you have nothing to compare it to. 

    

Edited January 29, 2020 by lucien216

[studiot]

You also need to be aware that there is already something called 'universal time', that has nothing to do with relativity.

It is based on what are called 'the fixed stars' which are so far away that their positions are 'fixed'  (ie does not change over human life timescales) on the 'celestial sphere' we base our astronomy on.
This is imagined to rotate at a fixed (average) rate around the Earth descibing what is known as universal time.

All human time measurements used to be tied back to this as a standard, but I think swansont may use something different nowadays.

[swansont]

1 hour ago, studiot said:

 All human time measurements used to be tied back to this as a standard, but I think swansont may use something different nowadays.

UT1 is a timescale based on earth rotation with respect to the distant stars. Similarly, we have GMT which is mean solar time tied back to the prime meridian at Greenwich. 

What the world uses is Universal Coordinated Time (UTC), which is the time derived from all of the government timing lab contributions to the BIPM. It's still sort of based on the stars, though. Even though it's generated from atomic clocks (the atomic timescale is TAI), it is occasionally corrected before there is a difference with UT1 that exceeds a second. That's why we have leap seconds.

 

3 hours ago, lucien216 said:

"It is the same event, but different amounts of time have elapsed since then as measured by different observers. "

Hhhhmm. This is what I wanted to hear. So you saying that the universe could be, say 30 billion years old, for some observers? So the age of the universe is only relative to us then?

Clocks that are moving or in a potential well will run slow relative to another clock not subject to those conditions, so they will see that less time has passed. Unless we are in some deep well that we don't know about, it's unlikely our time has been dilated by a factor of more than 2 relative to some other reference that could then measure 30 billion years. But a clock near a supermassive black hole in the center of a galaxy might have been dilated by a noticeable factor, and would think the universe is younger than 14 billion years.

[swansont]

25 minutes ago, michel123456 said:

 

1. If Relativity is used to describe the BB, how does it come that the result of the BBT is an  absolute number (~13BY ago) and not a relative number (~13BY before us).

We're doing the measurement, so those two situations are the same.

[Mordred]

Cosmology using the FLRW uses what is called a fundamental observer which is an observer whose time would be based on the mean average mass density of the universe. The universe we refer to is our Observable universe.

[swansont]

I was recently reading a claim that the kinematic time dilation difference between us and the galactic core is 1200 years (though I did not verify the number) for the age of the earth. The difference between our gravitational dilation and that of the mean mass density would probably be similarly small. So to the precision of the age of the universe measurements, there is no difference.  

 

edit: numbers roughly check out, though maybe it was 12000 years. Same issue of not being significant compared to the precision.

10^-3 c means a dilation of 10^-6, so a thousand years per billion. (I was doing this in my head while at the gym, so it's just a rough estimate)

[Mordred]

Correct we are close to the fundamental time afiak in so far as to being a good estimate. Though there is research showing we may be in an underdense region which leads to the discrepancy of the Hubble parameter it isn't conclusive at this point of research.

Edited January 29, 2020 by Mordred

[Strange]

This is relevant:

Quote

Earth's Core Is 2.5 Years Younger Than Its Crust, New Calculations Reveal

If it sounds impossible to you that the surface of our planet is actually older than its inner core, prepare to have you mind blown, because according to new calculations, the inside of Earth is actually 2.5 years younger than the outside.

https://www.sciencealert.com/earth-s-core-is-2-5-years-younger-than-its-crust-thanks-to-the-curvature-of-space-time

[jamesfairclear]

"TIME itself only came into existence at the moment of the Big Bang"

Time cannot be observed. Time is solely a human notion. The definition of time in Physics is “that which is measured by clocks”; that is all.

It makes no sense to state that an unobservable human notion came into existence before humans evolved. Such characterisations of the Big Bang made by well known scientific figures such as Stephen Hawking have been interpreted rather too literally. Such statements are really just a convenient way of stating that nothing is known about the state of the Universe prior to the Big Bang and that we may as well characterise it as the beginning of time. 

Special Relativity probably led to the characterisation of time as being a fourth dimension but in reality space/time is just a convenient way of describing a region of space along with its local gravitational field.

The measurement of time is simply the arbitrary quantification of a given set of events. There is a common misconception that time is something that actually exists as a fourth dimension independently to matter, energy and space and their various interactions (events). Time cannot be observed and there is no evidence that it actually exists outside of the confines of the human mind. When we measure time we are actually counting events such as the tick of a clock. The events are real enough but the interval of time we measure is best thought of as an imaginary interval between events.

Einstein concluded in his later years that the past, present, and future all exist simultaneously. He once wrote in a letter “ us physicists believe the separation between past, present, and future is only an illusion, although a convincing one”.

This view suggests that Einstein himself was not at all sure that Time was existential.

It is well known that clocks run at different rates according to the strength of the local gravitational field and the relative speed of the inertial frame of reference containing the clock.

Gravity and relative speed affect not only the frequency of ticks of a clock but also the frequency of all quantum events within a given inertial frame of reference. In other words the lifespan of all matter is subject to gravity and relative speed.

Whilst this variable lifespan of matter is typically characterised as the effect of time dilation it is more likely (in the absence of any evidence that time exists outside the confines of the human mind) that it is an effect on the forces acting between quantum particles.

[QuantumT]

I love this subject. Time in accordance to relativity.

If all aliens (incl. humans) in the universe gathered one place to establish universal time, it would probably look like the House of Commons during Brexit 😄

[Strange]

9 hours ago, jamesfairclear said:

Time cannot be observed.

Maybe you should invest in a clock.

9 hours ago, jamesfairclear said:

It makes no sense to state that an unobservable human notion came into existence before humans evolved.

So the universe was static and unchanging until humans came along? That sounds like a version of Last Thursdayism: the universe started evolving once humans came to be, and magically appeared to be 13.8 billion years old. Sounds implausible. 

 

[swansont]

12 hours ago, jamesfairclear said:

Special Relativity probably led to the characterisation of time as being a fourth dimension but in reality space/time is just a convenient way of describing a region of space along with its local gravitational field.

and?

Length is a convenient way of describing space, too. Is length also solely a human notion?

 

12 hours ago, jamesfairclear said:

The measurement of time is simply the arbitrary quantification of a given set of events. There is a common misconception that time is something that actually exists as a fourth dimension independently to matter, energy and space and their various interactions (events).
 

what about length. Does it not exist in empty space?

 

 

12 hours ago, jamesfairclear said:

Time cannot be observed and there is no evidence that it actually exists outside of the confines of the human mind. When we measure time we are actually counting events such as the tick of a clock. The events are real enough but the interval of time we measure is best thought of as an imaginary interval between events.

Again: same for length.

 

12 hours ago, jamesfairclear said:

It is well known that clocks run at different rates according to the strength of the local gravitational field and the relative speed of the inertial frame of reference containing the clock.

gravitational potential, which also includes position within the field.

 

12 hours ago, jamesfairclear said:

 

Whilst this variable lifespan of matter is typically characterised as the effect of time dilation it is more likely (in the absence of any evidence that time exists outside the confines of the human mind) that it is an effect on the forces acting between quantum particles.

Then you should be able to develop a theory based on this concept and measure this force, or effects based on it. (This requires overturning relativity, BTW)

 

[MigL]

On ‎1‎/‎29‎/‎2020 at 4:35 AM, lucien216 said:

If we do meet, or contact each other somehow, and want to compare our notes on the age of the universe. One of us will have to convert their units of TIME to achieve anything.

If we do this. I can only conclude that my 15 billion years is exactly equal to your 13.75 billion years. Because TIME is only what each one of us says it is.

No.
We may have different ways of measuring, but after conversion, the differences due to gravitational potential and relative motion will still be apparent.
The differences are sot an effect of different units of measurement.

edit:    I know, old post; but I had to correct this.

Edited April 7, 2020 by MigL

[Dave Enamu]

This is our perception of time maybe the universe doesn’t work in the way we want it to 

[joigus]

On 1/29/2020 at 8:50 AM, lucien216 said:

Hhhhmm. This is what I wanted to hear. So you saying that the universe could be, say 30 billion years old, for some observers? So the age of the universe is only relative to us then?

Very good question IMO. +1.

Not really. The key to this is what @Mordred suggested when he mentioned the key words "FLRW":

On 1/29/2020 at 2:08 PM, Mordred said:

Cosmology using the FLRW uses what is called a fundamental observer which is an observer whose time would be based on the mean average mass density of the universe. The universe we refer to is our Observable universe.

Then he went into a very interesting argument that really this co-moving time extracted from FRWL model (exact solution of GR) is actually an average and it would be affected by corrections due to fluctuations in density (+1). That's my understanding of what he said, at least. So there would be local underestimations or overestimations of the Hubble parameter (see below.)

<question for @Mordred>

Would an underdensity lead to an overestimation of H (and thus an underestimation of the age of the universe), or the other way around? I'm feeling a little confused right now (I think it depends on the global balance of omegas for DE, DM,...).

</question for @Mordred>

If the cosmological principle were exact, the FRWL solution would be exactly how the universe evolves, and the age of the universe would be (proportional to) the inverse Hubble expansion parameter.

\[\frac{a}{\dot{a}}=H^{-1}\]

Where

\[\dot{a}\]

represents the time change rate of the expansion parameter a, which in turn represents "how far away from each other typical galaxies are", and is dimensionless.

The Hubble parameter is the proportionality factor that tells us how fast a galaxy is moving away from us as a linear (directly proportional) function of its separation from us:

\[\dot{a}=Ha\]

Now, don't ask me why (ask @Mordred perhaps), but Einstein's GR allows you to re-scale time and expansion parameter at the same time for the whole timeline of cosmic events, if you want, but it doesn't allow you to mix both in this re-scaling.

So all you would be allowed to do is a re-scaling of both for the universe as a whole. Something like this:

\[dt'=\tau\left(t\right)dt\]

\[da'=\alpha\left(a\right)da\]

Where the primes indicate new variables and the d's indicate small increments.

So all observers would agree on a universal time that would be possible to re-define by re-scalings. Mind you, this is not your familiar wristwatch time. It's to do with the expansion rate of the universe. As others have pointed out, there are many kinds of time you can define, depending on what standard or physical process you use to provide you with the clock, so to speak.  When defining such standard clocks, you generally find observer-dependence. But as long as the FRWL metric is valid, it allows you to define a standard clock for all observers in the universe that are co-moving with the galaxies in the common expansion. You may re-scale such clocks, but all these galactic observers would essentially agree on it, because it's just the ratio of a and its time rate of change.

And t=0 goes to t=0 under any re-scaling. The origin of time, within the model, is absolute. The timeline scale is not. The deep underlying reason is that there is a singularity at the origin.

I hope that helps and I haven't made any gross mistakes.

 

[studiot]

Thank you for those useful points, joigus +1

[Phi for All]

!

Moderator Note

Several off-topic posts have been split to their own thread here: 

 

 

[Dave Enamu]

I’ve only recently joined this forum, and I’m not ashamed to say that a lot of this goes over the top of my head. I’m just an ordinary guy who sees things in a simple way and not all this gobbledygook I’m not clued up with all these equations. Let’s bring it down a level so us ordinary guys can join in. Another thing what’s with the names are they to make you sound mystical and magic - why not use your given names? Come on lads if you let the ordinary guy in it might open up a new world. So what d’ya say.