Markus Hanke

Yes, it is invariant under rotation about some real-valued angle (i.e. under a U(1) symmetry); the corresponding conserved current in Noether‘s theorem is called the probability current.

The angular momentum of a black hole is a property of the entire spacetime, and not of the singularity (which only arises in our models in the first place because we can‘t yet account for quantum effects). Furthermore, while spin can be considered a form of angular momentum, it is quite different from the one of macroscopic bodies.

A geometric relationship between reference frames in spacetime. In the simplest case of inertial motion, two reference frames being in relative motion quite simply means that they are rotated by a (hyperbolic) angle wrt each other in spacetime. Motion is purely a geometric phenomenon.

The gravitational field in the interior of a mass distribution such as a galaxy is not equivalent to the sum of gravitational interactions between discrete point masses arranged in a disk pattern. Also, I am pretty sure that General Relativistic effects cannot be neglected in this scenario, so Newtonian gravity is not the right theory to use. The model’s basic assumptions are fatally flawed, which is why no one in the scientific community is using it.

It’s battery operated (as I suspected), so the green light indicates that the battery is fully charged.

Distinction between what?

Yes, the magnitude and precise direction of the frame dragging effect does depend on the mass and the total amount of angular momentum of the central mass. It also depends on the exact shape of the central body, since rotating bodies are not perfectly spherical.

No. Causation does not imply intention. But then, it also does not preclude intention either - the question of whether or not there is a creator deity is outside the domain of the natural sciences. It is seldom a good idea to try and conflate fundamentally different domains of enquiry.

充饱 is usually used in the context of a battery being fully charged. So I guess this means that, when the green light comes on, the charging process is complete.

You will find all relevant answers in this excellent resource: http://stopmasturbationnow.org/

What SR says is that all observers agree on the separation between events in Minkowski spacetime. That physically means that all inertial observers experience the same laws of physics, which implies that such observers must be related via Lorentz transformations, and hence that measurements of space and time are observer-dependent, and not absolute. There is no absolute “past”, “future”, or “present” - there are only light cones associated with events, and their relative orientation in spacetime. This makes a concept such as “time travel” pretty much meaningless in this context.

The laws of the universe are found in statistical correlations between measurement outcomes. We perform experiments, measurements, and observations on aspects of the world around us - for example, we might measure the electrostatic force some distance from an electrical charge, and then do the same again at some other distance from the same charge, and so on. Given enough data points, a statistical pattern emerges, and that pattern is exactly the physical law that governs electrostatic forces for this particular setup. You repeat the same for more general setups, und you get more general laws. So the laws of the universe reside precisely in patterns that emerge from our observation of it.

The only way to “know” something is to go and experience it yourself. And even then you get only a subjective experience, filtered by your senses, and the way the mind processes information. So in that sense, there is only ever opinions and views. Since direct experience of something is not always possible, one can use logic to infer things. For example, I have not myself experienced the Second World War, but based on a various physical and non-physical traces it has left behind in the human world, many of which are accessible to me, I can infer with reasonable confidence that such an event has in fact happened. I still don’t “know” that it has happened, but the likelihood of it being just an illusion based on false inferences is negligibly small. The same is true in the sciences.

Actually, no. Being able to label the structure in the room as “table” relies on a lot of supporting conditions, some of which are very much subjective. For example, a member of some indigenous rainforest tribe who has never before seen a table, and does not even understand the concept of “table”, or has a word for table in his/her language (having no use for such a thing in his/her native environment), will not see a “table”. He/she sees only pieces of wood arranged in a certain fashion. Unlike you yourself, who sees a “table”. So clearly, a “table” being a “table” is not an objective fact, but a subjective perception, which is dependent upon prior knowledge and experience of the observer; if you’ve never before seen a table, you won’t recognise one as such. An objective description of the world would be one that is completely independent of the physical and mental structure of the observer who perceives that world. That is a very non-trivial undertaking, and arguably not really achievable in its purest form. This may seem like nitpicking, but actually has pivotal consequences.

Science is by its very definition a system to organise knowledge; since there are limits to what we can know - even in principle -, science will never be able to “explain everything” (whatever that actually means in real terms). In particular, physics concerns itself with building models of aspects of the world around us - its purpose is not to explain everything. We are quite far away from having a TOE; in fact, there are valid doubts over whether such a concept even makes sense. At the moment we are in the process of perfecting models that deal with what we can observe and measure, and, based on those models, make some educated guesses about things that we can’t. That’s about it. Like I said, the purpose is not to answer all possible questions, but to learn to ask the right ones to begin with - some questions are relevant to physics (and science in general), others are not. It’s actually pretty difficult. It was once considered a hard fact that the Earth is at the centre of the universe, and that everything else revolves around it. People thought it was totally obvious, and that was a reasonable state of affairs in the context of the technology and knowledge available at the time. The trouble is that “understanding”, and even perception itself, is a function of the human mind and consciousness, so distinguishing between what is objective and what is not, is far less trivial than would initially appear.

No such theory is possible, because EM dynamics are linear, whereas gravitation is not. They are fundamentally of a different nature. It depends what you mean by “chaos”. GR Gravity is completely deterministic, since it is a purely classical theory, but it is not always indefinitely predictable. Since gravity is highly non-linear, under certain circumstances you get chaotic systems - here “chaotic” is used in the sense that the evolution of such systems is highly sensitive to initial conditions. Even tiny perturbations of the initial conditions can have large consequences in long-term evolution of the system. This is a well known phenomenon, which is found in many other areas of physics as well. I don’t understand what you mean by this...? No instantaneous actions at a distance can occur in nature. You can only have non-local correlations, which is a different thing, because that does not allow for the exchange of information. Electromagnetism is completely local, there are no non-local interactions.

He was unsuccessful because gravity is not an electromagnetic phenomenon. His approach was basically upside down. This is not entirely true. It is in fact possible to combine GR and EM into a single, overarching model, called Kaluza-Klein gravity. The problem with this is that it can’t be done in 4 dimensions, and also that it requires extra fields for which there is no evidence in the real world.

I think the two mutually depend on each other - physics stimulates new discoveries in maths, and maths has a huge influence on how we think about the physical world. One might consider the relationship to be somewhat analogues to the Sapir-Whorf hypothesis for natural languages, albei probably more the weak version of it.

Apologies, I am unsure what you mean by this. What is your question?

The stochastics and uncertainties of quantum physics are intrinsic to its nature, they are not just an artefact of our observational methods.

That’s assuming that “I” is identical to consciousness or awareness...which is another assumption I’d be extremely sceptical of this particular assumption, actually...when I was a kid, my concept of “I” was very much different than it is today, yet I was aware of things in the same way that I am today. So equating “I” with the agent of awareness is something I’d put a huge question mark over. Also, when one actually stops the philosophising, trains the mind into a more phenomenological mode, and then starts to investigate where that agent/observer/knower really is, one very quickly realises that it is in fact nowhere to be found. There is nothing permanent and independent that you can point your “inner finger” at and say: “That there, that’s me.” There is only a whole bunch of memories, views, habit patterns, processes, and tendencies, none of which is separate from the context in which they originated, and all of which are just impersonal natural processes. The “I” is really nothing more than a view the mind takes on in order to make sense of these objects and their interrelationships. It’s not so much an illusion, as it is a case of mistaken identity - the “I” is just a vast and very complicated network of cause-and-effect relationships in space and time. These are completely impersonal, natural phenomena. It’s a bit like putting a candle in front of a rock, so that a shadow is cast. We can search for the “owner of the shadow” until the cows come home, but at the end of the day there is no one and nothing who “owns” it - it’s just light, and the absence of it. The same with “I” - there’s just a body interacting with the environment in various ways, and the mind pulling all of this together into a more or less coherent view of my body, my thoughts, my perceptions etc etc. But in reality these are all just impersonal process, and the “I” is nowhere to be found. That view is real, but it is also empty, since the object it refers to does not exist. It’s just a mental fabrication. Yes, but what question does this statement answer, really? We can only ever be aware of the contents of our own minds, i.e. mental objects of various kinds, including the end products of the processes of perception. Hence, the above is only to say that when there is awareness of something, there is mind - which is a rather trivial statement from a human perspective, albeit perhaps more interesting from a more general point of view. Then of course, there is also the question of whether or not the inherent subject-object duality in the notion of ordinary “awareness” is fundamental and irreducible, or in itself an empty illusion of some kind. Just because we sense our experience as being dualistic, does not mean that this duality is actually a fundamental feature of awareness itself.

It should be “There are thoughts, therefore there is thinking”. The “I” is an additional assumption, that may or may not follow - that’s up to the philosophers to debate.

Reported for (repeated!) trolling.

We have already established that one detector goes off, whereas the other one does not. Obviously, it will be the same with the explosives.

This applies to the neutrino, but not to the photon, which is demonstrably massless. If photons had a non-vanishing rest mass, several things would happen: Conservation of electric charge would no longer be guaranteed The Coulomb law would no longer be purely inverse-square; specifically, it would be weaker over large distances Static magnetic fields would show differences in behaviour On a more theoretic level, quantum electrodynamics would cease to be renormalisable, which is a big problem, since one could no longer extract any physical predictions from it. All these things can be experimentally tested, and to date no hints of any of the above has been observed, so very stringent limits have been experimentally placed on any non-zero photon masses. Note also that the photon having a rest mass would also bring down pretty much all of the rest of the Standard Model, which is obviously a problem.