joigus

19 minutes ago, dimreepr said:

Logic takes us to the most likely explanation from the available information; when it meets a paradox, it doesn't mean the paradox is real, it means the information is unavailable. Therefore logically, to draw the conclusion that logic is therefore illogical, is illogical...

Couldn't be bothered to read the rest.

 

Glad to see you gave speaking in riddles a rest.  👍 +1

What distinguises x to pair up with t? Why does this x go from -infinity to +infinity while y and z are compact?

9 minutes ago, NewScience said:

Can you see that this unifies gravity and electromagnetism into Spacetime?

No.

But there's worse: What happens to weak interactions and strong force? Are they outside spacetime?

1 hour ago, dimreepr said:

I'm not sure, it is mildly entertaining. 

Meh. I'm not sure I'm sure.

On 12/11/2023 at 8:02 AM, Eise said:

Well, if Dim is OK with the reactions he got, we better, close the thread, before a herd of 'oobermenschen' invades it... Otherwise, silence is the answer.

On 12/28/2023 at 5:29 PM, Janus said:

The same set of lines, just viewed from different perspectives.  In the first image the red line is "taller" than the green, and in the bottom image the green line is "taller" than the red.  The point being that in Relativity, time and space are measured more like the "height" of the lines in the images and not by their absolute length.

Brilliant.

This is my favourite way of talking about discrepacies in measured lengths and times for different observers, and I love that you just used it. Moving is like taking an angle. In fact, that's exactly what it is: Being at an angle with respect to another "mover". Somewhere else I've explained this as just another kind of foreshortening. Consequences of foreshortening are real enough for anybody trying to --eg-- get a large object through a short door by tilting it.

Of course, if you change your state of motion, your previous tilting parameter (your velocity) is no longer the same. This is at the core of so many people trying to "point out" to everybody else that "something is wrong" with relativity.

1 hour ago, zapatos said:

Wow!! That was awesome!! 😃

Thanks for the reaction. Yeah, I found out about this guy a couple of days ago on the Rick Beato channel, and I was blown away. 

The Bongo Song

Author: Safri Duo

Drum cover: El Estepario Siberiano

Last 1.5 min are promotional material

21 hours ago, studiot said:

I don't agree.

Neither do I. There are the vacuum solutions that you point out and they correspond to we all know what.

There are also interesting possibilities in the so-called topological vacuum solutions which would not be related to source charges.

I'm still trying to absorb the impact of "the spirals would be geodesics", or something equally daft.  

3 hours ago, William.Walker39 said:

and no theory based on a logical falicy can be correct no matter how many experiments claim to prove it.

Your physics is wrong for several reasons that have been pointed out. But here's another one: Logical fallacy implies a bad use of the rules of arguing in order to prove a point; it says nothing about being right or wrong regarding that point. 

Thus, even a theory based on false assumptions could be correct in the sense that it provides you with the right mathematical model. Ironically, that's what happened with Maxwell's theory of electromagnetism. He pictured mechanical tensions on a medium, which totally was the wrong idea, as later found out. But it gave the right equations, which in turn led to the right ideas that unfurl the amazing generalisation which is relativity, which you don't seem to understand.

For a less intuitive but more encompassing understanding of energy --if somewhat abstract-- one can't do better than this:

https://www.feynmanlectures.caltech.edu/I_04.html

Or, perhaps, one can. We have Emmy Noether to thank:

https://en.wikipedia.org/wiki/Noether's_theorem#Example_1:_Conservation_of_energy

When the mathematical dust has settled, the idea is: Energy is an abstract property of systems which they must have if 1) They can be described by a principle of least action, and 2) Physical laws cannot include time explicitly.

As we know both to be the case almost universally (cosmology being perhaps a case when things should be discussed more carefully), physical systems must have an energy.

28 minutes ago, Spring Theory said:

When the photon collapses, the charge source is the dipole that is created. I stipulate that every electric field implies a charge source.

That's not consistent with Maxwell's equations, only too obviously.

And I don't know what you mean by "the photon collapses".

A localised dipole produces a field that is zero-divergent everywhere. The total charge of a dipole is q-q=0. Any monopolar term cannot be accounted by the photon.

5 hours ago, Markus Hanke said:

If you think the phonetics of English are complicated, you should try German  Or one of the many tonal languages, such as Thai, or Chinese…

I tried with both German and Chinese. I had to give up on both, but I would recommend studying challenging languages if only to get an idea of the different ways in which information is organised in them. Chinese really was the biggest challenge in the sense that I realised I'd probably never become any fluent in it no matter how hard I tried taking it up that late in my life. 😢

25 minutes ago, studiot said:

A better example would be lather (voiced) and lath (unvoiced) and lathe (voiced)

Yes. Now is this difference enough to justify a different symbol? I'm not saying it is.

The phonetics of English is very complicated indeed. It's almost as if every word constituted a case study (that's obviously an overstatement, as there are regularities, obviously). But there are clearly many many irregularities, which must have to do with history.

I won't pretend I'm an expert on this, of course. I just like to think about these things. And English has taken a lot of my thinking and observing.

10 hours ago, Tristan L said:

Since when? The "th" in "rather" and the "th" in "with" are both pronounced exactly like the "th" in "the": as the voiced dental fricative. So "with the shovel" is pronounced with a long /ð/.

The vocal cords are vibrating when you pronounce "rather" while they're not when you pronounce "with" resulting in two very different sounds. Try it, and you'll see.

So, in answer to your question: Since the moment you pronounce them. Exactly as in "them" and "bath" (different).

I don't care what funny words any linguist uses to describe them. I've done an experiment, and in my book that is sacred.

26 minutes ago, Spring Theory said:

I'm proposing an underlying structure to charge that does not conflict with Maxwell's equations.

You could in principle make mass from non-mass. Charge doesn't work that way. For the reasons Swansont is telling you about. You need a divergence. IOW, source field lines to source out of a point.

Also, models based on ribbons with kinks and antikinks, and breathers, and many other topological properties have been done to death.

I don't see why it's deterministic (Planck's constant is zero?) Probabilities are kicked out of the picture?

I don't see how Lorentz's dilation equation could be made more precise either. More precise in what parameter?

What does it mean to do an autopsy on an elementary particle?

I cannot make sense of anything you say.

Normalisation should come first.

What is so suspicious about the motivation that you need an "actual motivation"?

Isn't the fact that physical parameters should be expected to depend on the length/energy scale at which you observe them enough motivation?

1 hour ago, Spring Theory said:

Current quantum theory is based on probability

No. It's based on amplitudes.

Probability comes from amplitudes. Amplitudes cannot be explained in terms of probabilities.

I hope you also notice that English doesn't identify a particular sequence of letters with a sound. Eg,

4 hours ago, Tristan L said:

but raðer wið regard to

(my emphasis)

the "th" sound in "rather" is very different from "th" sound in "with."

17 hours ago, studiot said:

Where did universal processes creep into the discussion ?

 

Sorry, because I was guilty of it.

Quote

• Universality is the observation that widely different microscopic systems can display the same behaviour at a phase transition. Thus phase transitions in many different systems may be described by the same underlying scale-invariant theory.

https://en.wikipedia.org/wiki/Scale_invariance

Quote

In statistical mechanics, universality is the observation that there are properties for a large class of systems that are independent of the dynamical details of the system.

https://en.wikipedia.org/wiki/Universality_(dynamical_systems)

Universality is frequently mentioned in association to scale invariance, not because it always happens, but because it seems to always happen in connection to critical phenomena.

13 hours ago, grayson said:

For those that do not know about the Alcubierre warp drive 

It rings a bell, yes:

https://www.scienceforums.net/search/?q=Alcubierre&quick=1&type=forums_topic&nodes=29

6 hours ago, Markus Hanke said:

I’m not aware of any such concept, at least not under this name.

Neither am I. Perhaps translation invariance @grayson?

6 hours ago, Markus Hanke said:

I’m afraid that’s not how spacetime curvature works. So long as you start with positive energy-momentum - irrespective of how this is distributed or oriented in space -, you’ll always end up with ordinary attractive gravity. This is not a question of position or orientation in space.

Agreed.

2 hours ago, Luc Turpin said:

So, self-similarity being synonym of scale invariance, both together forming a universal process in nature! correct?

It's a mathematical pattern rather than a process. I'm sure something like that is the reason behind @exchemist's excellent question.

Take. eg, principles of extremal time, action, length, etc. They appear everywhere in physics. It's more about a recurring mathematical theme than actually a particular process.

Keywords to look up:

Scale invariance and critical phenomena

Universality

https://en.wikipedia.org/wiki/Scale_invariance

It seems to be the case that when changes in structure formation are about to happen, a transitory stage characterised by scale invariance happens. An example is a gas about to make the transition to a liquid.

But, as noted, you could have some cases of self-similarity (synonym of scale invariance) when or where no phase transition is involved. Examples: biological tissue patterns, the shape of the coastline, etc.

Another kind of self-similarity seems to be in evolution itself, but not like a spatial pattern. Rather, as a pattern of embedded behaviour: A thing trying to pass on as good as possible a copy of its identity, with little things inside trying to pass on as good as possible copies of their identity,... up to a final level (chuncks of nucleic acid) of little things trying to pass on as good as possible a partial copy of their identity.

And so on, which seem to be relevant words here.

13 hours ago, J.C.MacSwell said:

13 hours ago, zapatos said:

I suspect the reason that blame keeps getting heaped on Israel more than Hamas is because Hamas is no longer rampaging through Israel, but Israel is still rampaging through Gaza. Every time someone kills a child they invite criticism. In the beginning of this most recent mess Hamas received the lion's share of rebuke. Now that Israel is on the offensive it is they who receive the lion's share of the rebuke. I personally don't find that surprising at all.

Once the fighting dies down I suspect there will be a more even-keeled evaluation of who is to blame for what. 

Expand  

You are probably correct.

Amen.

(Sorry for using Hebrew.)

And +1 to both.

On 12/17/2023 at 1:20 PM, KJW said:

That's only true in two dimensions. The corresponding quantity in four dimensions (ignoring the numeric factor) was given above:

R_ij^kl R_pq^rs δ^ijpq_klrs

For even dimensions in general, the quantity is:

R_ij^kl R_pq^rs ... R_uv^wx δ^ijpq...uv_klrs...wx

I am not aware of any corresponding quantity for odd dimensions.

 

Being a little fast and loose with your logic allows you to detect people who aren't.  

Welcome to the forums, if I didn't say it before.

18 hours ago, geordief said:

Is it just that there are some interactions where reversing the time signature in the maths  doesn't change the outcome?(I am fairly sure I have heard this more than a few times)

This sound more like the dynamical law is invariant under time inversions, which is quite different from saying that the direction of time doesn't apply.

Not even that is true, since electroweak interactions violate CP (charge conjugation + parity conjugation). Parity conjugation being the corresponding generalisation to quantum mechanics of mirror reflection. As we have very good reason to believe the world is CPT-invariant (the combination of the 3 relevant inversions in QFT), it follows that T must be violated.

As Genady said,

19 hours ago, Genady said:

As QFT obeys SR, there is direction of time in the QFT as much as it is in the SR.

Physicists sometimes like to play with metaphors, and conceptual hell breaks loose.  

When the metaphor constitutes the argument, you can rest assured the argument cannot be trusted.