# Thread: The Problem of Time leads to a Problem of Energy for the Universe

1. Originally Posted by James R
You know what I think? I think you made a mistake and $q_i$ is a position rather than a velocity. What do you think?

To me, $f_i(q)$ looks like a functional notation. That is, $f$ is a function rather than a number. Could that be correct?

So $\delta L$ has nothing to do with variational calculus? It's just a stock-standard change in L?

From your expressions, it looks like A is a vector three-potential - especially given your integral of $d^3 x$ rather than $d^4 x$.

Anyway, I plan to move on and discuss the first part of your post...
I will have to appeal to authority with two of these questions:

''You know what I think? I think you made a mistake and $q_i$ is a position rather than a velocity. What do you think?''

Susskind defines it as a velocity... I will watch the video again at some point to clarify this is indeed the case, but, essentially velocity turns up in the kinetic representation $T = \frac{1}{2} M \dot{q}$. Unless of course susskind has used the two were one is in fact the position given as q_i in which case I apologize. He couldn't have defined that well.

'' That is, $f$ is a function rather than a number. Could that be correct?''

I don't believe it is. Susskind clearly stated that $f=1$ in his lecture.

''So $\delta L$ has nothing to do with variational calculus? It's just a stock-standard change in L?''

Yup.

''From your expressions, it looks like A is a vector three-potential - especially given your integral of $d^3 x$ rather than $d^4 x$.''

I could be wrong, but I think you can miss out writing it as d^3 because when you take the quantity $\dot{q}$ it would imply a time component. It can be important to remember that A is a four vector because when you write out a matrix for instance, for an equation it swaps signs in the lower half entries.

2. I think I could have made a mistake in second light of q_i. I think q_i could have been a position. I will look more into it later and get back to you on that one.

Yeah... after a quick look, I am sure f=1... you can see this 16 mins in.

4. Looking back at what AN said

'' $q_{i}$ is taken to be the position of an object while the velocity is then $\dot{q}_{i}$. ''

It seems q_i is a position then, but susskind never defined this is what probably led to my confusion. I think that is cleared up now.

5. Originally Posted by Reiku
Looking back at what AN said

'' $q_{i}$ is taken to be the position of an object while the velocity is then $\dot{q}_{i}$. ''

It seems q_i is a position then, but susskind never defined this is what probably led to my confusion. I think that is cleared up now.
So now you know you should go with logic on this.

The universe is not timeless and devoid of energy.

6. Originally Posted by Cortex_Colossum
So now you know you should go with logic on this.

The universe is not timeless and devoid of energy.
Sorry, were did you get that from? I don't retract my statements at all and I never will until a satisfactory conclusions has been brought forwards. What you qouted me saying has nothing to do with the timelessness found in relativity. That was in conjecture to an energy-saving universe.

Anyway, the universe could very well be timeless in a global sense and because of this, there is an existing problem with energy since the two are conjugates of each other under Noether's theorem.

7. Originally Posted by Reiku
It seems q_i is a position then, but susskind never defined this is what probably led to my confusion. I think that is cleared up now.
You're basically admitting that the only experience you have of any of this is watching a YouTube video. If you'd worked through a book or a set of lecture notes then you'd be well aware of what various things mean, of alternative notation, of how things relate to one another. Instead when you say "I haven't seen that notation before" or the like what you mean is "That's not the notation used in this one video I'm using to answer your questions".

If the sum total of your knowledge on this stuff is from Susskind's video then how can you have been doing anything about the Dirac equation or gauge invariance or covariant properties of fields? All of them come after basic Lagrangian material and Noether's theorem because they make considerable use of it.

It isn't 'confusion' you have, it's just not knowing. It's like me saying I'm confused about Japanese. No, I simply can't speak it.

Originally Posted by Reiku
Secondly when you gonna give it a break with the (Wolf) claim AN? That was four maybe five years ago.
I think it's an excellent demonstration of your willingness to misrepresent what people say. Not to mention a demonstration of how poor your maths abilities were at a time you claimed to be studying Riemannian curvature in general relativity. Do you now admit you lied about that?

And your reply doesn't retort any of my demonstrations of your misunderstandings and mistakes. You also ignored my question. It's simple enough, perhaps 2 sentences, no LaTeX, to answer if you're familiar with this stuff. But if the extent of your Lagrangian understanding is from a single YouTube video that would explain why you made the mistake and why you can't answer the question.

Originally Posted by Reiku
If you more often spoke to me like a level-headed human, I would be more inclined to answer your questions.
I'm not asking you because I don't know. I'm asking you because I know and you claim to know but you have provided evidence to the contrary. I'm giving you the opportunity to step up and demonstrate your understanding goes beyond mangling a single YouTube video.

Would you like me to repeat the question?

Originally Posted by Reiku
Oh (and not just a level headed human)... you might also notice the fact you came in here with a whole load of accusations!!!!
Which I explained in detail and which you have yet to retort, despite being given many opportunities.

Would you like me to repeat the question?

Originally Posted by Reiku
Actually susskind did.

I said to the physics subforum that in physics there is a noticable difference between perpendicular and orthogonal. If you wanna keep that one going up then fine... I find it interesting that cptbork didn't even know of this definition when I spoke about it, upon which he said I was decieving everyone.
Firstly isn't a difference between perpendicular and orthogonal, they are synonyms. Secondly I was referring to the whole "matrix times matrix gives number" fiasco. Susskind said "equals one" and you took it to mean the number one, despite the fact matrix times matrix gives matrix and Susskind went on to explicitly state in the following 30 seconds or so he was referring to the identity matrix.

Originally Posted by Reiku
Disingenuous crap.

Guest is not a physicist.
Lagrangian methods, variational principles, integrals, functionals, partial differential equations, groups, transformations, these are all things most mathematicians cover in their undergrad. Remember, I did mathematics as my degree. I covered Lagrangian methods and variational principles in the first term of my second year. It was a required course so every mathematician covered it, not just those interested in mathematical physics. Similarly all the other things I just mentioned are considered essential learning and appeared in more than half a dozen required courses in the first and second years. As such even if Guest is a purest of the pure mathematician he'll know about this stuff.

Originally Posted by Reiku
Secondly, why choose two people who are completely pro-you anyway? Could you have picked any more of a biased set of individuals?
I picked two people who are definitely knowledgeable in mathematical methods in physics. It is a coincidence they happen to agree with me and disagree with you so much. In fact all of the people here educated to a high level in mathematics or physics are likewise.

Of course the fact they all happen to agree with me and disagree with you so much isn't really a coincidence. They, like me, see through your nonsense and dishonesty and hence don't hold you in very high regard. So it's not that I am picking biased people from the pool of formally educated mathematicians/physicists who post here but rather all of said people have concluded similar things about you.

Why, if you were to use the scientific method you might even consider that evidence for the hypothesis that you spout nonsense a lot. After all, while correlation does not imply causation it certainly warrants investigation.

Originally Posted by Reiku
Do yourself a favor, watch the video if you are even going to throw accusations about. It seems only fair, eh?
You make it sound like I've only pointed out one mistake. I've pointed out a plethora and all you can manage is a weak attempt at a single one, the rest you're just avoiding entirely, just as you did in the Dirac equation case.

Originally Posted by Reiku
I've just realized that what I said to James concerning why the potential depended on q isn't such a far off guess. See, the q takes on the form

$T = \frac{1}{2}m\dot{q}^{2}$
Guess? Why would you need to guess? The form of kinetic energy and potential energy in Newtonian physics is known to school children!

Besides, that expression for kinetic energy is not universally true. There's other systems with different kinetic expressions. You should have seen a number of them if you had worked through quantum mechanics and into quantum field theory. For example, the expression in the Dirac equation for kinetic energy isn't of that form. Can you tell me why it can't be of that form? It's to do with something I told you about the Dirac equation. Again, I'm giving you an opportunity to show you can do more than parrot back facts you've heard from YouTube, you can show you have an actual grasp of how all these things fit together. Here's a chance to show all my accusations are not as valid as they seem to be.

Originally Posted by Reiku
Susskind defines it as a velocity... I will watch the video again at some point to clarify this is indeed the case, but, essentially velocity turns up in the kinetic representation $T = \frac{1}{2} M \dot{q}$. Unless of course susskind has used the two were one is in fact the position given as q_i in which case I apologize. He couldn't have defined that well.
It's quite clearly position. Susskind explains it in the video, the context makes it obvious. Kinetic energy is written as $\frac{1}{2}m\dot{q}^{2}$ and obviously if q=x then $\dot{q} = v$ and so you get $\frac{1}{2}mv^{2}$.

You shouldn't have prompted me to watch the video because it really does become so obvious you're just parroting Susskind. For example, when James asked you what a Lagrangian density is you just spewed out the equation Susskind wrote on the board early on. Except you introduced an error because you wrote the second term in terms of $\dot{\phi}_{x}$, when it is actually $\dot{\phi}$. Anyone familiar with scalar field theory knows such a term doesn't arise in the case Susskind is talking about (if ever). You also spewed out the expression involving the photon field, the bit involving A, ie $\frac{1}{2}m\dot{x}^{2} + A \cdot v$. Susskind actually uses very poor notation there, because he writes the velocity in two different ways in the same expression because $v = \dot{x}$. He makes this obvious when he does the partial differentiation and hits both terms in the same manner. You transcribed this mistake. And I can see why you can't answer my question about T+U, Susskind explicitly states the implication involves more work and its something he doesn't want to get into at that point.

8. Originally Posted by AlphaNumeric
You're basically admitting that the only experience you have of any of this is watching a YouTube video.
Actually no I haven't. I actually know much more on the side than I do at the heart of the topic. I only spoke of the conservation in the form $\delta L = 0$ in such a form and no expressive mathematics. Even you as a compatent scientist will know that this expression is true, that Jame's questions led to one ''critical mistake'' as you call it. The rest of the claims were bogus, since even you said that ''I understand what Susskind means,'' which is actually indirectly saying that ''Ok, that is what he said and what you said but I understand what he means,'' is not admitting you messed up, but passing the buck of interpretation.

I would have actually much more appreciated the role James is taking, maybe one sympathetic to the fact I am actually trying here, but there you are, jumpimg in with a whole load, superfluous even set of arrogant accusations which have not summed up the situation once in entirity.

Give it a break!

9. Reiku, if you have such a fascination with physics, why don't you go study it at a university?

10. Originally Posted by AlphaNumeric
Susskind actually uses very poor notation there, because he writes the velocity in two different ways in the same expression because $v = \dot{x}$.
Thank you though for this. This is your stern stone cold way of saying ''yeh, he's telling the truth...''

...but I won't let you forget just yet the pick and mix of accusations you came in with. just like Tach in my Black Hole essay thread I am sure you would agree.

11. Originally Posted by Crunchy Cat
Reiku, if you have such a fascination with physics, why don't you go study it at a university?
I'm not located, believe it or not in any great accessible universities. Dunoon is hit by a serious money loss over this recession. Classes on physics is just not accessible.

12. Originally Posted by Reiku
I'm not located, believe it or not in any great accessible universities. Dunoon is hit by a serious money loss over this recession. Classes on physics is just not accessible.
You don't have to go to school in scotland, there are universities all over the world.

13. I live in a remote part of Scotland, and studying physics alone means I need to pay 10,000 pounds maybe more for my whole three years, but the worst part is, is that to get a bursary you need to study a maximum of three years with three types of subjects. I did that at college first of all, but I could not hold down all the studies of biology and chemistry on top of the physics, which weighed me down most of all, so I went back and completed physics alone, but I am in a quandry because they are the only sciences avaliable here and I am not qualified to do them all, and I only spent 6 months on a primilinary math course.

14. James

I defined before, just in case it is raised in your questions of the literature James, that I treat the mind as a subset of a larger system, a second set we call the universe.

Let us denote consciousness (and everything related to) as a set $\mathcal{B}$. Let the universe then be the set $\mathcal{A}$. Thus if $\mathcal{B}$ is a subset of $\mathcal{A}$ then I can write

$\mathcal{B} \subseteq \mathcal{A}$

It is taken for fact that $\mathcal{B}$ exists as a subset of $\mathcal{A}$ that it cannot be an exact copy. No subsystem can model precisely the larger system it is made of. This is conjectured because I believe that $\mathcal{B}$ can never contain all the information contained in $\mathcal{A}$.

So in case you raise any question on what I said and perhaps maybe forget how I really see all of this ''mind-stuff'', I will say the mind exists but the universe doesn't depend on the mind whilst the mind does depend on the universe.

Surely anyone will agree with that statement.

15. does'nt* depend on the mind... Jesus... totally wrote that wrong but fixed now.

16. The way my mind model of physics has a description at all concerning the universe is the low energy phenomenon of geometry. Known as Geometrogenesis, it explains why matter is required for carbon-based life form's for us, because, Consciousness is an improbability of the equations concerning high energy phenomenon, which does not even allow for subsystems.

The mind therefor arises from a stable spacetime, where matter is confugrated often close to their ground state energies that we call the brain.

17. . . . can someone define and give me a few proven examples of "negative energy" . . . humor me a bit here . . .

18. I have been thinking about alternative solutions to the time problem (which I have only just considered wondering about the clearup provided by AN concerning q) which is written into the archives of problems concerning unanwered paradoxes of physics. I decided that maybe there was an absolute field, maybe one single matter field where the time derivative does not vanish under the wheeler de Witt formalism [1]. I started to conjecture such a field and came up with

$\dot{\chi} = i(\frac{\partial \mathcal{L}}{\partial \dot{q_i}} \cdot d_) \nabla^2$

The time dependance is inherent in the matter field $\chi$ itself. The time derivative appears from $\dot{q_i}$ as well. So long as there are real dynamics with real matter (not photon energy or any energy pertaining to nullified particle trajectories [2]) - This tardyonic matter can act as Einsteinian Clocks and measure time passing inside the universe, using a matter field to be a real set of clocks, locally defining time.

In fact, the electron has an internal clock. Not many know this. Hestene's made a brilliant paper on this.

[2] Time for bosons are stretched to a hypothetical infinity suggesting that no time passes at all. It is a consequence of relativity itself (as AN knows, just for the benefit of others.)

19. Originally Posted by Reiku
I live in a remote part of Scotland, and studying physics alone means I need to pay 10,000 pounds maybe more for my whole three years,...
Nomally you would not be studying a sole subject alone but you would be majoriing in a subject (i.e. it's the one that gets the most attention and is the focus of a degree). Either way, 10,000 pounds for 3 years doesn't seem excessively expensive.

Originally Posted by Reiku
...but the worst part is, is that to get a bursary you need to study a maximum of three years with three types of subjects.
That would make sense as univiersities typically want their students to have a well rounded education. Why rely on a bursary? Get a student loan instead.

Originally Posted by Reiku
I did that at college first of all, but I could not hold down all the studies of biology and chemistry on top of the physics, which weighed me down most of all, so I went back and completed physics alone, but I am in a quandry because they are the only sciences avaliable here and I am not qualified to do them all, and I only spent 6 months on a primilinary math course.
This paragraph confused me a little. Do you mean that you could not handle a biology, chemistry, and physics class at once so you just completed a single physics class instead of all 3? I am also confused about your statement about being qualified for biology, chemistry, and physics. Does this mean you don't have the pre-requisite education to learn these subjects (as your statement about a preliminary math course implied?).

Biology and Chemistry typically wont require anything beyond algebra; however, physics will require a minimum of calculus. It's not uncommon for students to take calculus classes in tendem with physics classes, but if your math education is only preliminary then you will have some catching up to do.

Typically the heirarchy of math courses to calculus for your first few physics courses go something like this:

Basic Math, Alegebra, Geometry, Trigonometry or Pre-Calculus, Calculus (derivatives), Caculus (Integrals).

20. ''This paragraph confused me a little. Do you mean that you could not handle a biology, chemistry, and physics class at once so you just completed a single physics class instead of all 3? ''

Yes.

To qualify for a university I mean. I don't know what is required, but I doubt an insignificant understanding of math won't help, especially when it comes to qualifications, I mean.

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