What is the unit of space-time. of space it's the cubic-meter [ie volume], of time it's the second - but in the relativistic world of Einsteins making it must have had a unit of it's own [if it were to be seen as a single {new} entity]....... or did it feature in no calculations . If it did, what of things like say...density. Mass divided by volume in 'normal science' terms.....but in relativistic ones? [Mass divided by 'spacetime'?].
I've been told that matter is just really twisted up tightly knots of space -time, but if so how much space-time does one atom of hydrogen yeild if you unravel it. I know how much energy it blows of [it's mass times the speed of light squared] - but how much space-time can I get from it - a cubic meter for a hundred years.... a cubic mile for a thousand?
President of Peace? You fucking idiots!
....and the glory of the world becomes less than it was....
'Have we not served you well'
'Of course - you know you have.'
'Then let it end.'
IIUC, you can measure time in meters, or measure distance in seconds, depending on what you are doing. So space-time can be either meters-to-the-fourth, or seconds-to-the-fourth.
That's interesting WF - is the unit used in calculations, do you know? [I'd guess it must be.]
The thing about a shift to a new paradigm is that not only does it have to explain the anomalies that were thrown up by the previous one, but it must also include all of the areas previously explained. If it fails in this it is no advance. Thus relativity must be able to provide explanations for all of the 'dynamics' etc that Newtonian physics was capable of.........perhaps a waste of time, but you still don't hear much about that side of it.
President of Peace? You fucking idiots!
....and the glory of the world becomes less than it was....
'Have we not served you well'
'Of course - you know you have.'
'Then let it end.'
I need to get this right, last night I watched a Horizon episode about the nature of reality (from a physics rater than a human perspective {see qualia thread in Close}) in which top end physicists gave their opinions n the current state of it understanding. The first guy to speak began as follows. "Quantum theory is strange. Quantum theory says you can walk through that wall. It won't happen any time soon - but if you wait long enough it will."
This is as close an approximation as I can get to the guys actual words several hours later, but they are very close and certain aspects puzzle me. Firstly what in quantum mechanics would suggest such a thing to be possible anytime - surely it violates what we know about the nature of atomic nuclei, charge and force etc. Secondly, if such a thing were indeed possible (no matter how improbable at any given attempt) why should we necessarily have to wait (sic) - surely such an events occurrence would be 'uncertain' in its unpredictability of when it would happen. Why did the guy say "if we wait long enough" and not "if we try enough times"?
Later in the program they spoke of the 16 fundamental particles of the Standard Model and mentioned in passing that four of them were force carrying particles. What are these particles, does anyone know? Is the Higgs one of them and if so has it actually been confirmed by observation (I know there was talk of this but suddenly all is silence).
President of Peace? You fucking idiots!
....and the glory of the world becomes less than it was....
'Have we not served you well'
'Of course - you know you have.'
'Then let it end.'
Quantum theory does allow for walking through a wall. We know that matter at the quantum level exists as both particles and waves. Get a piece of paper and draw two dots on the paper, separated by a little distance. Now put a wavy line through each dot so that the wavy lines don't touch. This gives you a picture of two molecules--they are separated by space but also have a wave-like nature. As temperature decreases the wavy lines of those molecules will get "longer" until they actually touch. When those wavy lines touch is when things get weird--now the "wave equation location" of each molecule is overlapping, so you no longer have two molecules but one object covering the entire space defined by the intersecting wavy lines. Both molecules have become "delocalized". If we could delocalize ourselves then we would interact with other matter with quantum effects rather than macro effects so things like "walking though walls" would be "normal".
I have no idea what that would be like. I am not sure we could actually survive it if we took on quantum states rather than being limited to macro states. Quantum materials--superfluids and such--are weird (for lack of a better word).
Can I just check I've got this classification of sub-atomic particles right?
Fundamental S-A Particles------>Fermions [Quarks and Leptons of which there are 12]. Guage Bosons of which there are Four. The Higgs Boson in a class of it's own. The putitative graviton, yet to be discovered would fit in this set somewhere.
Composite sub-atomic particles------->Baryons [includes protond and neutrons], Mesons.
I know there are shed loads more actual and predicted particles out there but the above seems to be a manageable summary for me. It does however seem that the standard model is gathering more and more fundamental particle types and this is beginning to stretch credulity in it's complete acceptance maybe? Time for a re-think perhaps.
President of Peace? You fucking idiots!
....and the glory of the world becomes less than it was....
'Have we not served you well'
'Of course - you know you have.'
'Then let it end.'
Incidentally - the guy who was talking about walking through wall s was Leonars Susskind, Director of The Stanford Institute of Theoretical Physics and developer of the holographic principle, one of the leading contenders pertaining to the true nature of reality. One thing I could do with some help with is the concept of 'information'. It seemed to be a major problem that when matter passed beyond the event horizon into a black hole information was not conserved [lost?] - much more so than matter which was not even mentioned - and I wondered what this meant. The problem was ultimately circumvented by developing math that allowed the information contained in material passing into the black hole to be held at the event horizon, and it was this that led in turn to Susskind's proposal that the same could be the case at the Universes boundry. But what do they mean by 'information' in this context? Clearly more than just data or words on a page, but what exactly; Any ideas?
[edit; just found a wikipedia page on it. Things are a little clearer - it appears to be something to do with the distinguishing of one thing from another by virtue of all its attributes and properties etc.]
Quick extra question; presumably when matter goes into a black hole the mass of the black hole [which is already infinite if I understand what a singularity is] alters to a different class of infinity, in order that conservation of matter be maintained?
President of Peace? You fucking idiots!
....and the glory of the world becomes less than it was....
'Have we not served you well'
'Of course - you know you have.'
'Then let it end.'
Not all black holes are created equally; some of them are "larger" than others but in this instance "larger" really means "more massive". The actual singularity is only loosely real and can be thought of as "the point towards which matter is being drawn in". The intense gravity stretches space and has the side effect of making time slow down. If we could see something falling towards the singularity point of a black hole it would appear to get slower and slower the closer it go to the actual singularity; from that falling object's point of view we would all speed up.
The black holes at the centers of galaxies are massive. Really massive. It is possible for smaller ones to form but they would last anywhere from microseconds to a few minutes to only a couple of years.
If I remember correctly, black holes actually lose mass by radiating photon particles. I'm not sure how long the process lasts with small black holes before they disappear.
BTW, "singularity" doesn't mean they are zero-width. They have a size.
"Singularity" refers to the fact that density measurements go asymptotic in a black hole. Mass vs. Distince from Black Hole. Supposedly, mass has infinite density insice the black hole. But I think it's not a true infinite, just very big. Or it's infinite only in a different space/time reference than ours. Or something.
Anyway, the "singularitiness" of black holes is mathematical. It's this thing:
The gravity equations which first led to the idea of singularities do have a single r in the denominator, so a r approaches 0 the other effects approach infinity...but that doesn't mean they actually get there. What is does mean, though, is that reality is "open", from a topological point of view. Imagine a globe but now take away the point which denotes the North Pole. You may get as close as possible to the North Pole but you could never actually get to it even though it would be possible to get closer to it than you are now.
We talk about photons. The photons we see are those that fall within the wavelength of the visible spectrum of light. Does this imply that the whole em spectrum utilises photons, but just outside the limited range that our eyes are designed to see?
President of Peace? You fucking idiots!
....and the glory of the world becomes less than it was....
'Have we not served you well'
'Of course - you know you have.'
'Then let it end.'
. If it did, what of things like say...density. Mass divided by volume in 'normal science' terms.....but in relativistic ones? [Mass divided by 'spacetime'?]. 
