# How do you calculate an intuitive date and time from the BIG BANG to NOW? :-)

1. Sep 12, 2010

### Wulgulmerang

How do you calculate an "intuitive" date and time from the BIG BANG to NOW? :-)

For you Drum and Bass heads :-)

Unfortunately Professor Hawking is a busy man who cannot be a hub to the world. Until we can query his brain electronically that is.

Dear Professor Hawking,

Is it possible to calculate the "real" date and time, based upon the time from the BIG BANG to now?

For example the Gregorian Calendar says that it is currently Sunday 12th September 2010 20:58:34 to 1 second accuracy.

Is it possible to come up with a calendar signature that would reveal cosmological "real" time? I would like to write a program that calculates this every millisecond, as an alternative to the Gregorian B.C.E and C.E conventions.

Please could you shed some light on my thinking? Ideally it would be a simple way a reading the current time from the BIG BANG to NOW, in YEARS, MINUTES, SECONDS, and MILLISECONDS.

Do you think that I could use quantities greater than YEARS to make the calendar more readable e.g. would LIGHT YEARS make sense somehow?

Best Wishes,

Dave Kirkby.

If you'd like to hear a good drum and bass track. Search for B-Complex Beautiful Lies on YouTube :-) It's a "sick" tune! As Generation Y like to say.

Peace out to K-Pax (my favourite mathematical film).

You see, Professor Hawking's "might" like Drum and Bass. I like to imagine him rocking out to it in Cambridge Uni whilst thinking about Black Holes.

Last edited by a moderator: Sep 25, 2014
2. Sep 12, 2010

### Danger

Re: How do you calculate an "intuitive" date and time from the BIG BANG to NOW? :-)

Welcome to PF, Dave.
What you ask for is simply impossible, I'm afraid. The methods by which we try to determine the age of the universe do not lend themselves to anything approaching that level of accuracy.
I love the music in your link, so thank you for introducing it to me, but I'm not sure that it is appropriate for a serious science sub-forum. Perhaps you should delete it from this thread and re-post it in the General Discussion section. There are a few music threads there already, to which you can add it.

3. Sep 12, 2010

### Staff: Mentor

Re: How do you calculate an "intuitive" date and time from the BIG BANG to NOW? :-)

Welcome to PF.
As Danger said, scientific measurments always have some error margin associated with them and those measurements are the basis of the theory. So it won't ever be possible to know the timing of the Big Bang to that level of precision.
A light year is a unit of distance, not time. We can use scientific notation to relatively easily list the years.....billion isn't that big of a number anyway, though.

4. Sep 12, 2010

### MikeCB

Re: How do you calculate an "intuitive" date and time from the BIG BANG to NOW? :-)

What level of accuracy is possible?

Btw OP Light Years is distance not time

5. Sep 12, 2010

### diazona

Re: How do you calculate an "intuitive" date and time from the BIG BANG to NOW? :-)

Last I heard, the age of the universe was quoted as 13.7 billion years. I forget the exact uncertainty but I think it's around a couple hundred million years, so that's how precisely we know the current age of the universe.

6. Sep 12, 2010

### Staff: Mentor

Re: How do you calculate an "intuitive" date and time from the BIG BANG to NOW? :-)

According to the wiki on the subject, it is 13.75 ± 0.17 billion years.

7. Sep 13, 2010

### Wulgulmerang

Re: How do you calculate an "intuitive" date and time from the BIG BANG to NOW? :-)

Could anybody explain why the calculation is approximate to $$\pm$$ 0.17 billion years?

Are there satellites / NASA projects which seek to increase the accuracy of this measurement?

Thank you for making clear that LIGHT YEARS is distance.

Taking that onboard though, would it be reasonable to ask what the current "real time" distance is from the epicentre of the BIG BANG? That's changing all the time right?

8. Sep 13, 2010

### Chronos

Re: How do you calculate an "intuitive" date and time from the BIG BANG to NOW? :-)

We already are at the center of the big bang, as is every other observer in the universe.

9. Sep 13, 2010

### Staff: Mentor

Re: How do you calculate an "intuitive" date and time from the BIG BANG to NOW? :-)

Every measurement has an accuracy associated with it. That number is based on a measurement of the red shift and therefore distance and recession velocity of galaxies. Essentially, 13.75 ± 0.17 means the measurements (or the combination of all of the measurements) must have an accuracy of .17/13.75 = 1.2%
Yes.

10. Sep 14, 2010

### Wulgulmerang

Re: How do you calculate an "intuitive" date and time from the BIG BANG to NOW? :-)

I think there was a BIG BANG in my cerebral cortex after reading that.

I don't understand.

When dynamite/TNT explodes and the explosion is slowed down on video, you can clearly see an almost perfectly spherical shock-wave. Debris is scattered in all directions away from the epicentre of the blast.

What am I missing from my conceptual framework? (other than the 99.9% of things that could be put in a conceptual framework )

11. Sep 14, 2010

### diazona

Re: How do you calculate an "intuitive" date and time from the BIG BANG to NOW? :-)

That idea does throw everybody for a loop the first time Here's the difference: when you look at a TNT explosion, for example, the explosion takes place in a preexisting space, and the shockwave expands into that preexisting space. Every part of the explosive process can be located with respect to that space. But the Big Bang is different: it was the origin of space itself. There was no other space that existed "before" or "outside" the Big Bang, that you could use to identify the "location" of the bang. The only way to define any sort of location is with respect to the space that emerges from the bang itself. And since every location in that space started out from the bang (just as every part of the shockwave started out from the TNT), every location in space is equally entitled to be considered the center.

If you're confused by that, here's another way to think about it: imagine the process of zooming in or out on a picture, for example. The software you'd be using to zoom in or out basically just rescales the dimensions of the picture by some factor. The evolution of the universe is roughly represented by the same sort of process: there is a scaling factor that gets larger with time. Now imagine what would happen if the scaling factor were zero - that is, if you zoomed out to 0%. Every part of the picture would "collapse" onto the same point. (This is called a Big Crunch) Now imagine that happening in reverse: instead of collapsing onto a point, the picture (universe) starts as a single point and expands out. That's basically the Big Bang. Again, note that every point in the picture started out at the same place, and thus every point has an equal right to be considered the location of the Big Bang.

12. Sep 14, 2010

### Wulgulmerang

Re: How do you calculate an "intuitive" date and time from the BIG BANG to NOW? :-)

I kind of get the GIST of what you're saying. That there wasn't any space before the BIG BANG. It's just completely counter-intuitive. I cannot get my head round it. I keep visualising the BIG BANG as an expansion into empty space. I know that the empty space isn't there. But my mind keeps filling in the empty space with black space.

Is there a better way to explain this concept so that people do not fall into this pitfall?

It's the same for the BITMAP explanation. My mind cannot imagine there being no pixels around the collapsed image.

13. Sep 15, 2010

### Chronos

Re: How do you calculate an "intuitive" date and time from the BIG BANG to NOW? :-)

The big bang created curved space. But, it expanded so fast we will never see the backs of our own heads [due to the finite speed of light]. Our best observations to date indicate the curvature of the universe is nearly dead flat [i.e., enormous]. It is considered possible the initial 'singularity' that formed this universe was an infinitesimal part of a larger entity that is forever beyond our ability to observe.

14. Sep 15, 2010

### Wulgulmerang

Re: How do you calculate an "intuitive" date and time from the BIG BANG to NOW? :-)

So when popular scientists use the balloon to explain the BIG BANG, they're showing that the curved space-time which contains the stars and galaxies, is the surface of the balloon? (I am imagining a spherical black balloon). And when you say that the observable curvature is nearly dead flat, they're calculating that from the position of the furthest objects we can observe i.e. objects that are on the balloons horizon (13 billion light years away).

So what's inside the balloon?

15. Sep 15, 2010

### SHAMSAEL

Re: How do you calculate an "intuitive" date and time from the BIG BANG to NOW? :-)

It doesn't matter what's inside the balloon since what we define as reality, time and space are the surface of the balloon.

16. Sep 15, 2010

### Wulgulmerang

Re: How do you calculate an "intuitive" date and time from the BIG BANG to NOW? :-)

But there must be something inside the balloon. The galaxies and stars in space-time are on the surface of the balloon. If we look out to the horizon of the balloon, it's nearly dead flat.
What happens if move perpendicular to the horizon - if we move towards the centre of the balloon?

17. Sep 15, 2010

### diazona

Re: How do you calculate an "intuitive" date and time from the BIG BANG to NOW? :-)

That would be like moving perpendicular to space. It's a completely nonsensical concept. Can't happen.

To relate the balloon analogy to the actual universe, you have to keep in mind that the entire universe corresponds to the surface of the balloon only. There is nothing in reality that corresponds to the inside of the balloon. As far as the stars and galaxies are concerned, there is no such thing as "inside" or "outside" the balloon, since their entire existence is on the surface of the balloon.

18. Sep 16, 2010

### Wulgulmerang

Re: How do you calculate an "intuitive" date and time from the BIG BANG to NOW? :-)

So you're saying that all stars and galaxies only exist on the surface of the balloon in curved space-time. Intuitively I'm thinking that there's a thickness to it? But carrying on with the thread, because the Universe is expanding at the speed of light, if we travel towards the centre of the balloon, we're effectively treading water?

Stay with me guys. I'm sure I'll have a Eureka moment :-)

Saying that, the fact that there's a curved horizon in the observable Universe is pretty amazing. Most people think that we exist in a sphere, because of the spherical shape of stars and planets. But you're saying that we actually exist inside the surface of a sphere/balloon?

19. Sep 16, 2010

### diazona

Re: How do you calculate an "intuitive" date and time from the BIG BANG to NOW? :-)

umm... what? Not sure I get what you're saying there.

The universe is expanding, but not at the speed of light. At least, that's position-dependent: the apparent speed with which two points in the universe move away from each other is related to their distance.

Remember that the balloon thing is just an analogy. It's meant to show how something can be expanding without any particular point being the center of the expansion. But the surface of the balloon is two-dimensional, unlike our real universe, which is three-dimensional. We're not actually saying that the universe exists on (or inside) the surface of something.

20. Sep 16, 2010

### Wulgulmerang

Re: How do you calculate an "intuitive" date and time from the BIG BANG to NOW? :-)

Wilkinson Microwave Anisotropy Probe (WMAP)
http://en.wikipedia.org/wiki/Wilkinson_Microwave_Anisotropy_Probe

http://upload.wikimedia.org/wikipedia/commons/6/60/CMB_Timeline75.jpg" [Broken]

Shape of the Universe
http://en.wikipedia.org/wiki/Shape_of_the_Universe

Thanks Diazona :-)

From my point of view, if you're inside the surface of a balloon, and the surface has height, you're in 3D space.

I cannot imagine the shape of the Universe.

WMAP and Chronos suggest that the curvature is nearly dead flat. And that if the spatial curvature is close enough to zero, the radius of the flat space-time, is either at the horizon or beyond.

How can we live in a flat Universe? Doesn't flat imply 2D space? Can anybody on this forum contemplate the the true shape of the Universe. I know that special relativity makes this difficult. We're observing the past as we increase the distance. But can calculations compensate for special relatively and give us our best guess at the true shape of the Universe?

Last edited by a moderator: May 4, 2017
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