Markus Hanke

I find it difficult to fathom how anyone could claim that SR is inconsistent; after all, the relationship between inertial frames is given by a simple hyperbolic rotation. That’s it, that’s all there is to it - a rotation about some angle. Claiming that SR (between inertial frames) is inconsistent amounts to claiming that there are rotations that are not reversible. Can anyone show us an example of a rotation about some point and angle that is not reversible by counterrotating about the same angle? I guess not. Taking it further, beyond purely inertial frames, the claim of inconsistency would amount to saying that Minkowski spacetime permits violations of causality. While the formal proof of this one is more tricky, it should nonetheless be intuitively obvious that - since this spacetime is everywhere flat, and has a constant metric - no such violations are possible. This kind of discussion is just a waste of time, since the internal consistency of SR is not under any kind of contention. The only point that one could possible argue about is the question of whether SR is a good and valid model of the real world. Given that no violations of Lorentz invariance have ever been observed, it stands to reason that it is indeed a good description, at the very least within the domain of applicability that we can currently probe. And that’s a pretty wide domain.

These links are examples of publications that either do not appear in peer-reviewed journals, have been falsified during peer review, or are based on erroneous assumptions & misunderstandings of what SR is actually about. To name just two examples - viXra is not a peer-reviewed journal (anyone can publish anything there, so it is of no scientific value), and Stephen Crothers is a known crank and crackpot, devoid of any scientific credibility. What I am trying to say is that you need to be more careful in choosing your sources. On the other hand, it is scientific fact that no violations of Lorentz invariance (the symmetry that underlies the theory of relativity) have ever been observed: https://en.m.wikipedia.org/wiki/Modern_searches_for_Lorentz_violation Relativity is evidently valid within its domain of applicability. Obviously, that domain is limited, just like for any other model of physics. For example, Newtonian gravity is valid in the weak-field, low-velocity domain, but fails miserably outside of this. Likewise, we expect relativity to break down also at some point, presumably in the domain of quantum gravity. That does not make it wrong though, any more than relativity makes Newton wrong; it’s just a question of getting the domain of applicability right.

Not in mainstream physics, no. However, there are speculations and hypotheses - mostly in the realm of metaphysics and philosophy - which consider the question of whether our sensed “flow of time” is an artefact of our perception/brain, rather than a fundamental part of nature. I don’t think this type of speculation belongs into this thread, though. This is true, but there is a caveat - the notion of “gravitational potential” can only be meaningfully defined in spacetimes that admit a time-like Killing field, whereas time dilation arises directly from the metric. So I would argue that time dilation is a more general concept than gravitational potential. But of course, in Schwarzschild spacetime the two concepts are largely interchangeable, due to the symmetries present here.

Yes, that is one of the special cases I mentioned. Again, this is true only for special cases (such as Schwarzschild-type metrics) There is not really any such thing as a “rate of time flow”. Time dilation is not something that happens locally, it is a relationship between clocks in spacetime. Locally, all clocks always tick at “1 second per second” - it is only when you compare two or more clocks in spacetime that you can meaningfully speak of time dilation.

And yet you appear to take no issue with using a computer - apparently oblivious to the fact that its integrated circuits were designed by people who were educated in quantum mechanics and electromagnetism, built by people who were educated in engineering and mathematics, and marketed to you by people who were educated in economics/marketing/management. It was packaged by machines designed and built by engineers, delivered to you (or your local store) in vehicles built on the principles of thermodynamics, and probably paid for using networked systems programmed and administered by computer scientists. If the education of the people who made that computer you are now typing and reading on possible was a sad affair and brainwashing, then please feel free not to make use of the end product. And all other products of the modern world which are the result of the efforts of educated...sorry, meant to say brainwashed...people. But since you evidently do, I can only surmise that you are a in fact here only to troll us, because you aren’t taking your very own principles very seriously, do you? And that is what I really call a “sad state of affairs”. You need to realise that yes, creativity is indeed important, but without scientific knowledge to give it a firm basis, it can never produce anything of any practical value, beyond the most trivial of contraptions. The secret is hence not to foster an attitude of “creativity vs science”, but rather to realise that both are needed to make a real impact on the everyday life of ordinary people. Truth be told, this made my day lol

This general type of thing is called “anecdotal evidence”, and, while it may sometimes appeal to us (confirmation bias!), it carries no scientific value whatsoever. That is because its defining characteristic is its being anecdotal, meaning it cannot be independently subjected to the scientific method.

I think there may just be some confusion here about what these interactions actually mean; essentially, and very simply put, the different interactions are based on different types of charges which particles carry. Electromagnetism is an interaction between electric charges, so it affects anything that carries electric charge. The strong interaction describes the interactions between colour charges, which are carried by quarks and gluons. The weak interaction arises from a type of charge called weak isospin. Some particles carry more than one type of charge - for example, quarks have electric charge, colour charge, and weak isospin; they thus interact electromagnetically, are bound by the exchange of gluons, and can change flavour via the weak interaction. Therefore, an atom is held together and made into what it is via a complex interplay of all three fundamental interactions; however, under normal circumstances these interactions are nonetheless physically distinct mechanisms, and which one of them prevails depends largely on scale and type of particle involved. So for example, the quarks inside protons and neutrons are bound mostly by the strong interaction, whereas electrons are bound to the atomic nucleus mostly by electromagnetism (and the general laws of quantum mechanics).

Electromagnetism has nothing whatsoever to do with the weak and strong interaction.

No, because gravity does not behave the way electromagnetism does, so you can’t model gravity by trying to reduce it to electromagnetic interactions - except perhaps as an approximation in the Newtonian regime, which is basically what this author has done. The trouble with this is that gravity is not actually a force at all - it’s geodesic deviation, and hence a geometric property of spacetime. What this author has done here is re-create a Newtonian approximation; that is fine, but I don’t really see the point, since it is only an approximation in the low-energy, slow-velocity regime. The full behaviour of gravity, as described by General Relativity, cannot be modelled in this way.

The thing with this is that gravity is not actually a force, and even if it were, it does not behave anything like electromagnetism.

White holes (which are a speculative entity) are part of maximally extended Schwarzschild spacetime - which is a stationary solution to the field equations. This simply means that white holes - if they exist - do not decay.

The rotating object would “drag along” object B in its direction of rotation (frame dragging), so that object would gain orbital angular momentum as seen by a far-away observer. Whether it would itself start to rotate around its own axis is a question that is not so easy to answer, since the two-body problem in Kerr spacetime is a notoriously difficult problem. I don’t know what you mean by “dynamo effect” though, as that usually refers to how magnetic fields are generated.

Spacetime is the set of all points in space at all instances in time, along with the geometric relationships between these.

1. This forum supports LaTeX, so you could have just typed them using LaTeX code. 2. You should have posted this in the “Speculations” section of the forum, not in “Physics” 3. As for the actual contents - are you open to an honest assessment, or did you post this in the hopes of receiving only positive feedback?

Classical physics yes, Newtonian physics no. Like Strange has already pointed out, Newtonian physics operates under the assumption that there is an absolute time, so obviously there cannot be time dilation of any kind. Gravitational time dilation is purely a GR effect. This is not true in general. Gravitational time dilation arises from the g{tt} component of the metric tensor, which, in the vicinity of a source of gravity, is a non-constant function. Only if the spacetime in question is both spherically symmetric and stationary, is there a correlation between gravitational time dilation and escape/free-fall velocity. Schwarzschild spacetime is one example for this, but it is not true for other types of spacetime.

It would be just an artefact of how our brain works, i.e. how it builds up a model of experience. Specifically, I would say it is one of the many mechanisms by which the mind constructs a sense of self. After all, how would you build a self construct if it turns out that there isn’t actually an agent that can affect change, such as free will?

Good point!

If only it was as simplistic as you think it is First of all, quantum physics is both completely deterministic and stochastic. What is deterministic is the evolution of the wave function - given any initial wave function, you can predict with certainty how that wave function will evolve over time (assuming you know the respective boundary conditions etc). However, what is stochastic is the relationship between the wave function, and physical observables - observables are represented by hermitian operators, and which of their eigenvalues you actually measure is - in general - purely probabilistic. For example - you send a stream of photons through a double slit. Given knowledge about the initial conditions (slit separation, photon frequencies, etc) you can predict with certainty what kind of an interference pattern you are going to get on your screen at the end of the experiment. However, you can not predict precisely where each individual photon will hit the screen, that is purely probabilistic. And we’re not even talking about the question which slit each photon goes through. So this is your third possibility - it’s come to be called “determined probabilities”. That’s the first thing. The other thing then is that determinism does not imply an absence of free will, and conversely, indeterminism does not imply that free will is necessarily possible. There are four different philosophical positions that encompass the four possibilities here: hard determinism, compatibilism, hard incompatibilism, and libertarianism. You can look these up yourself. The main point here is that this an ongoing debate, and there is no consensus about which is the correct one. And just to top things off - the human brain is a macroscopic system, and as such classical. So one would expect it to be deterministic. In reality however, in spite of its classicality, it is an example of a complex non-isolated, non-linear, chaotic system. So even if it were completely classical (which actually it isn’t anyway, since it’s fundamental building blocks are quantum mechanical), you still couldn’t predict its precise state very far into the future, because it is extremely sensitive to initial and boundary conditions, never even mind way too complex to mathematically model with currently available technology. It’s also an open feedback system, since it continuously receives external inputs, and generates responses that can modify those very inputs. So is the brain deterministic? You decide yourself, based on the above. Whatever your conclusion, what does that imply for free will? Again, you decide yourself, based on the philosophical positions on this subject matter. I think it is safe to say that there are no straightforward answers either way here.

Try any basic introduction to the cognitive neurosciences. As others have pointed out already, we know about the process of visual perception in quite considerable detail. You might start with Wiki on this subject: https://en.m.wikipedia.org/wiki/Visual_perception

Another excellent post by Janus...+1.

It can’t, because no such thing exists. The best you could possibly do is use the notion as an approximation in a small local region, for slow speeds and low energies. For example, the inhabitants of Madrid and Barcelona could very roughly be said to share the same “now”, since they are close together and presumably are not in the habit of moving at relativistic speeds wrt to each other.

Unless my understanding of this is badly flawed somewhere (which I can never entirely rule out), then the answer is yes, fermions interact with the Higgs in a manner similar to gauge bosons. From what I remember this is implemented in the (unbroken) Lagrangian via a Yukawa coupling term between the fields. When you break the symmetry, this leaves behind mass terms in the new Langrangian.

It should also be remembered that mass arises from a quantum field’s interaction with the Higgs field, so in some sense it isn’t actually an intrinsic, isolated property at all. Prior to electroweak symmetry breaking, all elementary particles were massless.

I can throw a few more theories into the mix, if you like We’ve quite a selection to choose from!

What it models is 4-dimensional Minkowski spacetime, which is precisely - you guessed it - Special Relativity. What are you hoping to achieve by denying the basics of one of the most studied and well-tested model in physics? This is standard undergrad stuff.