# Is There A Universal Now?

Discussion in 'Physics & Math' started by Cyperium, Jun 14, 2022.

1. ### Neddy BateValued Senior Member

Messages:
2,546
One clock is fine for keeping track of time. However, it is not very scientific to call what it measures a "Universal Now," because without another clock to compare it to, you have no way of knowing whether the time is universal or not.

"Universal Now" implies that everyone everywhere can agree that whatever time is on your one clock could also be the time on all the other synchronised clocks located everyplace else in the universe. You must have at least two synchornised clocks to check whether the time is truly universal by checking whether everyone everywhere can agree that at least those two clocks can be synchronised. It turns out that not everyone agrees that they are synchronised, so the time is not a "Universal Now."

If you don't understand what I posted, you should ask a question about it. It is not a quilt or a pattern, it is a clock synchronisation process which shows you how two clocks can be synchronised in one reference frame, but not synchronised in a different reference frame. The key concept is that the speed of light is a constant which is not affected by the motion of the source.

Last edited: Aug 25, 2022

3. ### Write4UValued Senior Member

Messages:
19,970
And our knowing makes a difference?

There is not even a single clock that keeps Universal time. There is only an existential chronology of NOWs, whether we like it or not.
The Universe itself doesn't give hoot about what we think or know.

5. ### Write4UValued Senior Member

Messages:
19,970
By using a quilt of relative twin time patches, no?

Last edited: Aug 25, 2022

7. ### Write4UValued Senior Member

Messages:
19,970
Finally, you are getting it. I am not doing SR. Relativity happens between constituent parts (twins) inside the universe. The Universe as a singularity has no twin moving relative to itself. There is only NOW.

The point is that the singular wholeness has a single time frame and experiences a chronology of NOWs over its entire geometry.

You talk as if time is an extant dimension that the Universe is moving through. It isn't. Time is an emergent property of duration of existence. Time does not exist in the future. In the future there is only a timeless dimensionless permittive condition.

To the singularity every time frame that is older than NOW lies in the past and there can never be a timeframe younger than NOW. That would lie in the future and there is no time for a future event until the universal future becomes the universal NOW.

Last edited: Aug 25, 2022
8. ### Michael 345New year. PRESENT is 72 years oldlValued Senior Member

Messages:
13,077
What exactly would one clocks be keeping track of?

Try - accurate clocks keep in close synchronisation with the agreed measurement of our notation of time units

Write4U likes this.

Messages:
19,970
NOW?

10. ### Mike_FontenotRegistered Senior Member

Messages:
622
That explains everything.

Now, we can talk about what's really important: how to set up an array of clocks and helper friends (HF's) for an ACCELERATING observer, analogous to the array of clocks that Einstein showed us how to set up for an inertial observer. The reason that is important is that the array of clocks tells us something about "NOW-at-a-distance" that must be accepted as real and fully meaningful to the observer. The array of clocks never gives us the answer quickly or easily (but other methods do) ... the value of the array of clocks method is purely to establish the meaningfulness of the answer.

Details are given in

https://vixra.org/abs/2206.0133

and its references.

11. ### phytiRegistered Senior Member

Messages:
732
Michael 345;

Not for you, and why time is relative to the observer.
There is one occurrence of an event but many perceptions.
The events exist in the form of images, so the solar flare you saw 10 min. ago hasn't been seen yet by the alien on Saturn, or a camera on a space probe in the same vicinity.

You need the additional distance info to know the emission time of the image based on your detection time.
The finite light speed is the basis for SR with it's relative measurements.

The observer's now consists of a sphere of images arriving simultaneously.
Assume the first stars were formed within a short interval of 'astronomical time', we can consider simultaneously. Consider a circular slice centered on the observer, containing stars A thru D. For simplicity they are shown in the same direction. Images are emitted at the small circles when the light has reached the distance of the next inner star. D at t=0, C at t=1, etc. The images arrive simultaneously at t=4. The stars are approx. the same age, but the observer sees them as they were at different stages of star evolution.
The rest of the story includes those beautiful images of Hubble and Webb telescopes, showing the large clouds of gas where stars are born. The universe has been forming a variety of objects since its beginning. All objects can’t be the same age.

12. ### Write4UValued Senior Member

Messages:
19,970
Wow, all that to explain the event of a universal NOW? Well, that is beyond my understanding of an abstract measurement of an immeasurable property. You are going to determine the advent of NOW by comparing two immeasurable NOWS from inside the Universe? How does that work? How many NOWS are there?

And if you tell me there are an infinite number of NOWS, you are admitting you have no clue when the Universe's NOW IS !

Last edited: Aug 26, 2022
13. ### phytiRegistered Senior Member

Messages:
732
Mike;
The propagation speed of light in space is c. The measured speed of light in any inertial ref. frame is c. Clock synchronization requires the observer to apply the method.
The 'home' observer can calculate the space and time coordinates for the distant frame using the transformations , but that is based on an assumption of no change in the relative velocity, which can only be verified with an observation.

14. ### phytiRegistered Senior Member

Messages:
732
Neddy;

If there are no observers, who makes the measurements and interprets them?
...
Einstein originally thought simultaneity explained length contraction but it can't explain reciprocity of observations without a physical lc.
Minkowski developed spacetime diagrams for his 1907 4D SR.
Green B frame rod passes black A frame rod, blue line is light path.
Left, without lc:
A measures B rod = A rod.
B measures A rod =e/f, or d/(gamma)^2. Not reciprocal.
Right, with lc:
A measures B rod = d/gamma.
B measures A rod =e/f, or d/gamma. Reciprocal.

15. ### Write4UValued Senior Member

Messages:
19,970
But that is not the question!
The question is not if every object in the Universe has its own NOW . The question is if the Universe has its own NOW.

Inside the Universe every atom has its own NOW , but that has nothing to do with the NOW of the Wholeness in which all relative NOWS appear and disappear.

The Universe is a single expanding object (world volume) that has a singular existence. Nothing inside the Universe affects the existence of the expanding singularity.

I understand the concept of looking back in time. But all that is inside the universal singularity. There is nothing that precedes the Universal NOW. It's impossible to look past the Universal NOW into the future.

Outside the universe there is only a timeless, dimensionless, permittive condition of NOTHINGNESS.

Last edited: Aug 26, 2022
16. ### Neddy BateValued Senior Member

Messages:
2,546
Let me ask you... Do you feel that distance is something which requires an observer to exist? Like, if no person observed and measured the diameter of the earth, then the earth would not have a diameter? Of course that would be nonsense.

It is the same with Special Relativity. For example, the the twin scenario does not require actual twins, or actual people. It would work the same way with only clocks instead of twins. We know that it works as predicted with muons, for example.

Last edited: Aug 26, 2022
17. ### Neddy BateValued Senior Member

Messages:
2,546
That is a problem, because it is SR that tells us that there is no universal now.

Mike_Fontenot likes this.
18. ### Neddy BateValued Senior Member

Messages:
2,546
Yes, I agree that a clock measures our preferred time units. Some clocks use a format of 12 hours AM per day, and 12 hours PM per day. Other clocks use a 24 hour per day format. We could invent a clock that just measures seconds, starting at whatever number we choose, and then we could watch the number displayed get larger and larger without bound. Does any of this matter as to whether there is a universal now?

I understand your position is that time is not a thing that has any properties. It does not have a color or a mass. You cannot put it in a bottle and store it for later. It is not "stuff". I agree. Does any of this matter as to whether there is a universal now?

19. ### Neddy BateValued Senior Member

Messages:
2,546
I don't understand this statement. There is no difference between using a Minkowski diagram as developed in 1907, or using the Lorentz transformation equations that Einstein used in 1905.

Measuring the length of an object which is stationary is easy, as you can just put a measuring stick next to it and see how long it is from one endpoint to the other. Measuring the length of an object which is moving is more difficult. You have to locate the two endpoints simultaneously. Since it is moving, you would get an incorrect length if you located the rear endpoint today, and then located the right endpoint two days later. So obviously it is critical to have a definition of simultaneity which allows you to located both endpoints at the same time, and that is Einstein synchronisation of clocks.

Last edited: Aug 26, 2022
20. ### Write4UValued Senior Member

Messages:
19,970
That is why I don't use SR, it is a useless exercise. It cannot yield a definitive answer to the OP question.

This is a perfect example of a fractured science. Of course, the universe has a NOW. It had a beginning and will have an end and in between there is a measurable chronology of duration of existence. The arbitrary value of the incremental measurements is irrelevant.
For our convenience we have assigned 13.7 billion years worth (and counting) of NOWS to its existence.

du·ra·tion
noun
1. the time during which something continues.
"a flight of over eight hours' duration"
Oxford Dictionary

What happens inside the Universe is totally irrelevant. Just as what happens inside an airplane is irrelevant to the duration of flight.

There is nothing inside or outside the Universe that can prevent it from existing as an independent object in toto.
Even if the Universe will gradually lose its energy (entropy) the wholeness itself will continue its singular existence.

If it contracts and returns to a small singularity (bouncing universe) it may just start the BB all over again for eternity.

As long as "something exists" there will be a NOW (incremental time value) associated with the duration of its existence.

Time emerges with duration or change of existence. It doesn't exist independent of "duration" of something.

Last edited: Aug 26, 2022
21. ### Michael 345New year. PRESENT is 72 years oldlValued Senior Member

Messages:
13,077
The detail of it (whatever the event) not being seen does not mean said event is still in existence

Not a great deal if anything. However I was correcting what I consider a incorrect statement - clocks measure time time. Since the statement was made in the thread Is There a Universal Now silly me thought it should be replied to and, as already mentioned, corrected in the same thread. Happy for you to contact moderators to have my post moved to where you consider it should reside

Not totally incorrect understanding

I'd say my position, more a considered opinion which no poster has shown not correct, to this moment, but whatever

Again if you feel my post belongs at / under another thread feel free to have it moved

22. ### phytiRegistered Senior Member

Messages:
732
Where is the universal clock?

23. ### phytiRegistered Senior Member

Messages:
732
Bx is the axis of simultaneity, so B is measuring the ends 0 and e at the same time!