Friday, August 30, 2013

"Causal dynamical triangulations"

This video is part of a larger Nature article titled "Theoretical physics: The origins of space and time". Subtitled "Many researchers believe that physics will not be complete until it can explain not just the behavior of space and time, but where these entities come from."
Casual dynamical triangulation uses just two dimensions: one of space and one of time. The video shows two-dimensional universes generated by pieces of space assembling themselves according to quantum rules. Each colour represent a slice through the universe at particular time after the Big Bang, which is depicted as a tiny black ball.

 

Causal dynamical triangulations


bill stroud said...     
Of course it would seem that language was never intended to provide such meaningful terms that identifies the actual state or state transitions. After all its the structure of language where precise (imprecise) terms create paradoxes. The truths exist in domains that language will never describe. When we can communicate at a level that language never can, we will begin to assemble these elusive truths. Language is a member of the Darwinian set of rational.

29 comments:

chickelit said...

Never express yourself more clearly than you are able to think.

~Niels Bohr

ndspinelli said...

Did you science guys ever get laid in your youth?

ndspinelli said...

Things I'm curious about: A South Carolina couple were arrested in a Charleston Home Depot having sex in a prefab storage shed. I'm curious in knowing do you think this is part of a long term relationship?

chickelit said...

Nick, stop channeling Titus.

Eric the Fruit Bat said...

Having only recently found out about The Big Bang Theory, there are still a great many episodes I have yet to watch.

Still, I've not seen or heard even the slightest hint of a physics-based double entendre.

That pleases me greatly.

Way too easy.

Way too sleazy.

Eric the Fruit Bat said...

(1) The girl next door, literally.

(2) Speaking of way too easy, see what I mean?

deborah said...

(Dude, like that was some good shit.)

As I understand it, there was no time before the big bang.

Eric the Fruit Bat said...

Time is God's way of making sure that everything doesn't happen all at once.

deborah said...

Time is one damn thing after another.

chickelit said...

If I understand deborah, there was no time for foreplay before the Big Bang.

Eric the Fruit Bat said...

Everything may have begun with a bang but it will end with a wimper.

Eric the Fruit Bat said...

I was going to do a link to Squeeze performing one of my favorite songs, "Bang, Bang," off their first album but our internet filter seems to think it's pornography.

Oh, well.

That said, if it's pornography, at least it's catchy, humorous pornography, so I say good for it!

deborah said...

No pube trimming either.

XRay said...

All well and good... but what I want to know is what's on the other side of the CMBR. Nothingness for eternity, no time nor space, what would be the language used to describe that. Or, am I making a conceptual error.

rhhardin said...

It takes courage to read past this

Even in completely empty space, they found, an astronaut undergoing acceleration would perceive that he or she was surrounded by a heat bath.

rhhardin said...

Space is nature's of keeping everything from happening to you.

William said...

Space, time, and gravity are the bane of my existence.

Revenant said...

Interesting stuff.

Crimso said...

Einstein maintained that if all matter and energy were removed from the universe, then space and time would cease to exist. Matter and energy cause space-time to exist, but space-time dictates how matter and energy "behave." Not that Einstein was always correct. The whole thing is plunging me into an existential crisis which can only end in solipsism syndrome. That will result in a 3 day weekend jag of World of Tanks. By Tuesday, I'll be back to abnormal.

Trooper York said...

I am worried about this new tag "Stuff Lem is curious about."

Are we going to have to have a bunch of posts about vaginas and green cards and muscatel?

XRay said...

I wish to hell someone had answered my question. I know there is enough smartness here to do so.

deborah said...

https://www.youtube.com/watch?v=wrCk5ZWt3a8

ad hoc said...

How does the Big Bang Theory account for the accelerating universe? If there is an explosion at t=0, then maximum acceleration would occur just after that. You would see expansion and deceleration. But, the universe is expanding and picking up speed. I realize that Newtonian physics don't fully apply, so are there properties of dark matter that account for the acceleration? Just wondering.

Revenant said...

How does the Big Bang Theory account for the accelerating universe? If there is an explosion at t=0, then maximum acceleration would occur just after that

Despite what its confusing nickname would lead you to believe, the "big bang" wasn't an explosion.

When (for example) a stick of dynamite explodes, the chemicals within the dynamite rapidly convert from solid form to gas. Gas requires a much larger volume than solids do, so the molecules that had previously been part of the stick of dynamite are forcibly pushed apart: boom.

In the case of the big bang, space itself expanded, bringing the contents of the universe along for the ride. The singularity didn't explode; it was ripped to shreds, metaphorically speaking.

Unfortunately there is not, so far as I know, a consensus on WHY the universe's expansion is accelerating.

Revenant said...

I wish to hell someone had answered my question

The cosmic microwave background is a remnant of when the universe was much smaller and hotter, before it cooled enough for hydrogen to form. The "other side" of the CMBR would be the early universe -- basically an opaque swirl of incredibly high-energy particles and heat.

deborah said...

Rev, the go-to guy :)

XRay said...

Thanks for the answer.

So then what was the "space" surrounding the universe when it was smaller and hotter. And, after the big bang, wouldn't that space, whatever it consisted of, still be on the other side of the observable universe, or CMBR if you will. Or, is what you are saying is that the opaque swirl of particles and heat is what is eternal and goes to infinity. Our universe but a bubble within it.

Aridog said...

Moar stuff for Lem's curiosity.

deborah said...

Xray, I think the whole idea is there was no space or time outside of the universe, either when it was quite small or after the big bang. All space and time occur within the universe. Time can only occur when there is distance to be traversed, and the distance is a function of time.

But for a comforting explantion of why their is no outside of the universe, consider the moebius strip:

"A Möbius strip made with a piece of paper and tape. [Take a strip of paper, give it a half twist, and join the ends with tape.] If an ant were to crawl along the length of this strip, it would return to its starting point having traversed the entire length of the strip (on both sides of the original paper) without ever crossing an edge.

http://en.wikipedia.org/wiki/M%C3%B6bius_strip