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Everything posted by Markus Hanke
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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.
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Isn't 'science' education" actually brainswashing?
Markus Hanke replied to Taingorz's topic in Speculations
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 -
Does physics say my notion is incorrect?
Markus Hanke replied to discountbrains's topic in Modern and Theoretical Physics
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).
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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.
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Does physics say my notion is incorrect?
Markus Hanke replied to discountbrains's topic in Modern and Theoretical Physics
The thing with this is that gravity is not actually a force, and even if it were, it does not behave anything like electromagnetism. -
Question about gravity, frame dragging, and the dynamo effect.
Markus Hanke replied to DandelionTheory's topic in Relativity
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.
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DERIVING THE G CONSTANT (A GYROCENTRIC MODEL)
Markus Hanke replied to Robert M. Evans's topic in Speculations
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.
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are there more views than deterministic and indeterministic
Markus Hanke replied to empleat's topic in General Philosophy
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? -
are there more views than deterministic and indeterministic
Markus Hanke replied to empleat's topic in General Philosophy
Good point! -
are there more views than deterministic and indeterministic
Markus Hanke replied to empleat's topic in General Philosophy
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
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Another excellent post by Janus...+1.
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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.
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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.
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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.
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I can throw a few more theories into the mix, if you like We’ve quite a selection to choose from!
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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.
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I have not stated any “ideas”, only the current scientific consensus. Whether you think that I “know what I am talking about” or not is irrelevant to me. What you get is an interference pattern, which is a distinct entity from the wave function itself, since the pattern is formed by a distribution of individual hits. No it can’t. In fact, the exact opposite is the case - the interference pattern looks the way it does only because spacetime in the region of the apparatus has Minkowski geometry, and is hence flat. If the region between the slits and the screen had a non-trivial spacetime geometry - specifically, a gravitational wave field (i.e. your “time\space waves”) of sufficient average amplitude -, the interference pattern on the screen would look quite different. The other problem of course is that, if you were to measure which of the slits the electron moves through, the interference pattern disappears - even if nothing changes in the geometry of spacetime. So it’s trivially evident that the pattern has nothing to do with the geometry of spacetime, but arises from the wave-particle duality of the quantum system itself.
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As already stated earlier, relativity is a model of spacetime. The two are not different things. Special Relativity is just Minkowski spacetime, General Relativity describes any semi-Riemannian manifold (=spacetime) that is a solution to the Einstein equations. As for the physical interpretation of spacetime itself, it is simply the set of all events, i.e. all points in space at all instances in time. The theory of relativity simply describes how these events are related to one another.
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Both relativistic quantum mechanics, as well as quantum field theory are special relativistic models, i.e. the work on a Minkowski spacetime background. So no, it is not restricted to classical theories. Going even further, String Theory is formulated on a smooth and continuous spacetime background, the geometry of which must be described by the field equations of General Relativity.