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[alway]

Finally, IIRC, Einstein considered it "his gretest mistake", including the Cosmological Constant (or whatever he called it, I think I'm mixing up my terminology, in my haste to not be ninjaed with further replies while logic-checking) to keep the Universe from collapsing, before we knew how the universe was expanding...  But if Dark Energy is true, we might well have something very similar anyway.  The chances that it's the same thing is small, but if Einstein had more than just the vague idea of "it keeps the Universe from collapsing" in mind, when he thought of it, he might have been onto the right track.  Sorry, being a bit rushed in my explanations, so I can bet my bottom dollar that someone's going to tell me I've misremembered this. 

The problem was, Einstein was bringing preconcieved notions of 'how the universe should work' to the table in both cases, instead of closely examining 'how it does work.' Though he was intellectually honest and admitted such mistakes after he was shown to be wrong rather than digging in. He seems to have essentially come at things with a similar train of thought as many up to that point including Newton; the idea of a static, unchanging, deterministic clockwork universe, mostly originating from philosophical ideals relating to 'how the universe should work.'

[Leafsnail]

No. String theory is a bunch of nonsense pushed by Michael Kaku as true when in reality he has no basis for it whatsoever while he peddles it on the "History" Channel.

There are a lot of believers in it, but I'm not one of them.

I don't believe in it either - it's not experimentally proven.  But it does unite quantum mechanics and relativity in a consistent way, showing that the two don't have to be contradictory.

[Heron TSG]

Except for all of the arbitrary assumptions and whatnot - the number of dimensions, etc.

[10ebbor10]

Just one thing I would like to add, as I'm typing this on Android e -reader.

Relativistc theorem describes fast moving objects.
Quanntum describes small objects
Quantum field dynamics describe fast small objects.

In this case Rel and. Quantum. Are both genrralizations of the third theorem. Whille they do say different things they don't conflict, as they are both parts of one larger theorem.

Some people want to find one theorem of everything.While this would be a nice find,ifit exist, it would.be rather useless.


On the matter of dark energy/matter.

Ther's a problem with it. Several galaxies have been discovered that could not exist with dark matter alone,suggesting that something else, like different laws for microgravity might be in effect
N
Example. ....'s ant (I forgot the name).

Thr universe is a grid of white tiles. The ant moves over this grid, changing the color as it hits a tile Android moving right on a black tile and. Left on a white tile.

Now you know the univeersal law for this simple universe, can anyone tell mme. Whad the ant. Will do whitout running the simulation or looking it up on the internet.

[Darvi]

Or, to sorta-quote Sheldon Cooper, "I didn't invent them, they were there all along!"

But imo the worst about the string theory being correct is, if gravitons or whatever does gravity, were strings, people would call them g-strings. That hypothetical pun is so bad it made my brain hurt.

[MonkeyHead]

Just one thing I would like to add, as I'm typing this on Android e -reader.

Relativistc theorem describes fast moving objects.
Quanntum describes small objects
Quantum field dynamics describe fast small objects.

In this case Rel and. Quantum. Are both genrralizations of the third theorem. Whille they do say different things they don't conflict, as they are both parts of one larger theorem.

Some people want to find one theorem of everything.While this would be a nice find,ifit exist, it would.be rather useless.


On the matter of dark energy/matter.

Ther's a problem with it. Several galaxies have been discovered that could not exist with dark matter alone,suggesting that something else, like different laws for microgravity might be in effect
N
Example. ....'s ant (I forgot the name).

Thr universe is a grid of white tiles. The ant moves over this grid, changing the color as it hits a tile Android moving right on a black tile and. Left on a white tile.

Now you know the univeersal law for this simple universe, can anyone tell mme. Whad the ant. Will do whitout running the simulation or looking it up on the internet.

Langdon's Ant. Good example of long term emergent order, especially once it reaches the "diagonal highway" phase of its behaviour.

[alway]

The point isn't full knowledge of every moment of the universe; that is not possible for more reasons than just complexity. It's more a case of:
There is an ant moving around. What's it doing? Hell if I know; but I'm curious, so I will watch it and try to figure out.

Aside from curiosity reasons, anything that can be tested, as I stated before, can result in an effect not predicted by theories preceding it; and this is a tautology owing to the fact that 'testing' is just a fancy word for 'observing for an effect which would not occur based on the null hypothesis,' with the null hypothesis in this case being the proven predecessors. These effects could range from useful things we can use for technology to unknown dangers to anomalies muddying the outcomes of other applications or experiments. By definition, a testable theory is useful in describing the universe.

[Starver]

Or, to sorta-quote Sheldon Cooper, "I didn't invent them, they were there all along!"

But imo the worst about the string theory being correct is, if gravitons or whatever does gravity, were strings, people would call them g-strings. That hypothetical pun is so bad it made my brain hurt.

The stealth/unintended/terrible pun that comes to my mind, at the forefront (or, rather, a little over the edge of the accepted forefront) of Physics concerns "Branes", in "M-Theory" that have been called "M-Branes", i.e. "Membranes", with only a little extra tongue work (ooer, missus...).

(Langton's Ant, BTW.  And as 10ebbor10's Android looks like it messed up the text a little: The rule is that on each square that it arrives, it flips the colour (black<->white) and turns left/right according to what that colour was[1], before stepping forward one unit and repeating this rule from the start again.  Also worth checking out "Rule 110" (or 30, or one of the others) for a 1-dimensional (although often represented with successive iterations, i.e. time, in the perpendicular direction, to form a grid) automata.)

It may be a trite example, BTW, but there's philosophical connections made between cellular automata and "the universe" represented by at least one of the XKCD strips.  (Critique it, if you will, but that's not the point.)


[1] Or is, doesn't really matter; or indeed which colour meant which way, because it'd just produce a mirror image pattern if you got it 'wrong'.

[alway]

The M from M theory can stand for a number of different things; Membrane is one of those things.
http://en.wikipedia.org/wiki/M-theory#Nomenclature

[kaijyuu]

C) travelling backwards through time (at FTL speeds)

My understanding is you wouldn't actually go backwards in time, but rather you'd go into the imaginary number range (square root of -1, and all that). Which would be all kinds of silly.

[Il Palazzo]

C) travelling backwards through time (at FTL speeds)

My understanding is you wouldn't actually go backwards in time, but rather you'd go into the imaginary number range (square root of -1, and all that). Which would be all kinds of silly.

so... we go to itime?

will apple patent that?

Heh. Very nice, good sir.

[alway]

C) travelling backwards through time (at FTL speeds)

My understanding is you wouldn't actually go backwards in time, but rather you'd go into the imaginary number range (square root of -1, and all that). Which would be all kinds of silly.

Imaginary time actually is a thing. http://www.hawking.org.uk/the-beginning-of-time.html
Not as silly as you thought, heh.
It's actually a really interesting concept Hawking has helped pioneer, and actually avoids many of the problems of infinity brought about by using "real" time. It's a great tool they have used to investigate things which in real time are singularities, and is tied in with the 'no boundaries' postulation which hypothesizes physics works the same everywhere.

It seems that Quantum theory, on the other hand, can predict how the universe will begin. Quantum theory introduces a new idea, that of imaginary time. Imaginary time may sound like science fiction, and it has been brought into Doctor Who. But nevertheless, it is a genuine scientific concept. One can picture it in the following way. One can think of ordinary, real, time as a horizontal line. On the left, one has the past, and on the right, the future. But there's another kind of time in the vertical direction. This is called imaginary time, because it is not the kind of time we normally experience. But in a sense, it is just as real, as what we call real time.

...


In fact, James Hartle of the University of California Santa Barbara, and I have proposed that space and imaginary time together, are indeed finite in extent, but without boundary. They would be like the surface of the Earth, but with two more dimensions. The surface of the Earth is finite in extent, but it doesn't have any boundaries or edges. I have been round the world, and I didn't fall off.

If space and imaginary time are indeed like the surface of the Earth, there wouldn't be any singularities in the imaginary time direction, at which the laws of physics would break down. And there wouldn't be any boundaries, to the imaginary time space-time, just as there aren't any boundaries to the surface of the Earth. This absence of boundaries means that the laws of physics would determine the state of the universe uniquely, in imaginary time. But if one knows the state of the universe in imaginary time, one can calculate the state of the universe in real time. One would still expect some sort of Big Bang singularity in real time. So real time would still have a beginning. But one wouldn't have to appeal to something outside the universe, to determine how the universe began. Instead, the way the universe started out at the Big Bang would be determined by the state of the universe in imaginary time. Thus, the universe would be a completely self-contained system. It would not be determined by anything outside the physical universe, that we observe.

I recommend reading the whole lecture I linked. It's not too long, as Hawking isn't one for exquisite soliloquies and overindulgent monologues encapsulating tomes of meaningless pleasantries and redundant retellings.

[kaijyuu]

Yet you still insist the universe is anything other than batshit insane


That explanation sounds like some sort of mirror universe thingamajig.

[alway]

Well, no, it actually simplifies things and effectively smooths out the weird into an easy-to-use topology of space-imaginary time which can then be transformed back into normal space-time.

[MonkeyHead]

Its not that the universe isn't batshit insane. It just doesn't run on what the human brain assumes is common sense.