joigus

I know this from a documentary by Iain Stewart.

I need a coping mechanism right now.

I don't have a very sophisticated knowledge of this. I can distinguish two types: a priory probability (when you have a knowledge about the make-up of the system. In that case, you can predict the probabilities. Laplacian probability for the proverbial die being just one example of a system in which, from symmetry, you can infer equiprobability. Other example is quantum mechanics, in which you have a dynamical law (the Schrödinger equation) which allows you to predict the probability density. It doesn't have to be always symmetry. Mathematics makes all this a lot less vague, of course. In the case of pre-bigbang scenarios, the statistical hypothesis would come from extrapolations of the known physical laws that are particularly 'natural' or 'simple'. And I do know how vague terms as 'natural' or 'simple' are. But I also think you can get an idea of what I mean by that. The other version of probability is the phenomenological one. You reproduce the experiment over and over again, and get an idea of how sound your probabilistic hypothesis is. This is the kind of concept that universe, and time itself with it, is not amenable to. The example you mentioned of the Monsoons is one that perhaps resists a simple criterion. On the one hand, Monsoons are regularities, but OTOH, there are exceptions. We know Monsoons fail from time to time. Now, please, tell me about the third one.

Very interesting questions. Give me some time to ponder and then react, please, because I think an attempt at an answer to that must have to do with a subtle distinction that some people make between aprioristic probability and empirical probability. I would like to say more on that, hope we're not getting too off-topic, and would be interested to know your opinion, as well as other users'. I would also be very interested to learn what @Eise makes of all this.

So, what's your answer to the perennial question, If a tree falls in a forest...?

Trying to answer to @Intoscience's question 'what's your take on this?', and leaving aside the ongoing discussion based on the nonsense of spacetime being a scalar... I understand 'emergent' as a variable that's derived from relationships among more fundamental variables, and it's not present in those variables. Very much what Swansont stated. It is derived from the overall dynamics of those variables. The variable that's really bothersome, especially when trying to combine cosmology and quantum mechanics is time, not space. Because: The universe cannot be instantiated/re-instantiated There were no observers* [?] No really good explanation for initial conditions of the universe Meta-laws (laws previous to physical laws as we know them): What does 'previous' even mean? Time, in combination with QM, really seems to stand in the way of anything meaningful we might try to say in very early cosmology. It's not a practical matter for everyday physics. It's about very early cosmology. That's precisely why most prominent physicists who are concerned with cosmology support the view that spacetime, or maybe just time, is emergent. Namely: it hides something in it, so to speak; it derives from a more fundamental, structure. The three questions, time asymmetry, chiral asymmetry, and charge asymmetry in the universe must be related, as the CPT theorem of quantum field theory relates them all very clearly. If/when we find out why time is a one-way pathway, because we get to understand how it emerged that way, we will probably understand the other two. Maybe it's something completely unsuspected. Maybe instability and spontaneous breaking of symmetry are at the core of why we perceive the universe as a history, the actual underlying level being something much more symmetric, and observers only making sense as stretched over time. I'm approaching my dangerous 'push the envelope' mode. * The now popular view of measurement as decoherence between alternatives doesn't even start to tackle this problem IMO, as irrespective of whether the universe is in a mixed instead of a pure quantum state, a quantum state for the whole universe doesn't make a lot of sense, at least with the usual operational rules that go with it. This is the problem of the pointer states, can be formally swept under the carpet for anything other than the whole universe, but is clearly posed in Wheeler & Zurek.

You keep saying tensor... It's not like the 10th time you say 'tensor' it becomes one. OK. I'm tired. Maybe tomorrow.

Massive or non-massive. It's just that we don't know of any spin-1/2 massless particles. Think of helicity and chirality as elementary-particle versions of the property of a corkscrew: Normal corkscrews are right-handed; if you rotate it in the clockwise direction, it goes downwards. Left-handed particles are like the corkscrew that you see in the mirror. The area per unit time swept by the line joining a and b is the angular momentum per unit mass, and it's conserved (Kepler's second law). No mystery there, I guess.

No, spin in the direction of motion more like. Although not exactly. There is a property of an elementary particle called helicity. It is the (normalised) projection of spin in the direction of momentum. \[ \lambda=\frac{\boldsymbol{S}\cdot\boldsymbol{p}}{\left|\boldsymbol{S}\cdot\boldsymbol{p}\right|} \] When studying massive spin-1/2 particles, one introduces another similar quantity that has to do with handedness. It's called chirality, and only in the limit of v-->c (approaching the speed of light) both observables coincide. Chirality is a bit more subtle. It has to do with handedness (whether you have a given 'right' version of the particle or its mirror image). It's made up of so-called gamma matrices from the Dirac equation.

Yeah. Sorry. Right. Here's the correct statement: Only left handed electrons couple to the weak force. Same happens to quarks. So left and right handed electrons (and quarks) are treated as different particles in the standard model. It's neutrinos that exist only in left-handed version. I think I got it right now. Thank you, Swansont.

Deviations from Kepler's laws for Mercury are due to \( \frac{1}{r^3} \) terms. Gravity is very different from Coulomb's law at strong fields. The right statement would be: gravity with general relativity, locally, is no force at all.

Gravity is an inverse-square law only in the weak-field approximation.

Gravity is not a force (at least not on an equal status with the other forces): https://physics.stackexchange.com/questions/33875/gravitation-is-not-force https://www.scientificamerican.com/article/the-illusion-of-gravity-2007-04/ Gravity is dimensionally exceptional, which makes it unwieldy to quantisation. Gravity is entropic. Gravity can be coded into the geometric properties of space time so that it locally 'disappears'. I don't think it's the most primal of forces. It's a very different animal.

Any machine that handles the void variable 'I'?

We aren't. Civilisation is a moving standard. We will look uncivilised and barbaric to our offspring far down the line. Unless Mad Max was a prophecy.

I'm not sure your model explains Newtonian gravity either. You haven't told us much about it.

Again, I applaud your enthusiasm. But science is tightly constrained by observation. It's not just about opening your mind's eye. It's about doing that while keeping an eye on observational data. Here's a list of features you haven't contemplated (not meant to be complete): We know all massive particles to be chiral (they have handedness). All electrons in the universe are left handed. Composite particles are coupled by chromodynamic forces and decay by electroweak forces. Hadrons, e.g., (strongly interacting particles) cannot split apart into quarks, but by forming other hadrons. But they're free at short distances! This is due to forces that look nothing like gravity. On the other hand, your model doesn't even capture many of the properties of gravity that we know already, like gravitational lensing, or deviation from Newton's law at strong fields ('violation' of Newtonian centrifugal barriers), or black holes. All the features coming from GR.

LOL. Cm'on. No Inca monkey gods there. It's the standard model Lagrangian. And OP said he wanted his model to be the starting point to explain all of physics, including the standard model. Nature is messier than we sometimes want to believe.

Agreed.

I think religion came about from a deep instinct in humans to manage the land by trying to understand it in faltering steps and ill-conceived guesswork. But religion has a life of its own, and further evolves from that first drive into self-perpetuating structures that no longer have to do with their first raison d'être. Perhaps it played a role in the origins of civilization. But it no longer does.

One I can think of is getting hold of a vast library of nucleic acids and proteins. Biology is also a resource. Also, vast reservoirs of methane in oceanic bottoms, molecular oxygen, which is rare in the universe. Or simply ground to settle. Tidal and volcanic energy that maybe they --but not us-- can wield. Who knows. If you look back at the history of human exploration, the driving force was the acquisition of resources. Adding to knowledge for its own sake was kind of an afterthought.

I don't think civilization ever advances as a result of religious principles being applied. The iconic fantasy of an advanced civilization visiting us is very much a literary mechanism to evidence our own imperfections. But I don't think that any actual intelligent alien species that we may find some day will respond to any of our utopian dreams. Most likely --if that ever happens--, they will be looking for resources.

That assuming they don't see us as food, no matter how advanced they are. I can only hope they can't synthesize pepsin.

The hummingbird really gave it away! I wouldn't say a touch of genius, but definitely a clever one.

Funny, but I think you've misspelled 'melodious' rather than 'Byrds'.