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I don't think that information access will be the issue of the future. It is the declining ability of folks to use it.

Indeed. The same is true also with power - all the major decisions which affect humanity globally (eg starting wars etc) are made by an extremely small group of individuals. Who has decided that this would be a great system?

Well, the fundamental assumptions underlying this solution are homogeneity and isotropy - if you feed this kind of energy-momentum distribution into the field equations, you get as solution a spacetime that expands. You are free to choose yourself what kind of coordinate system you wish to use to describe this, but obviously it is smart to use a system where your intended calculations are easy. I understand what you are trying to say. The FLRW metric does rely on the cosmological principle, that’s an assumption we make - that on large scales the universe is homogenous and the same in all directions. Since there’s an observational horizon past which we can’t see, it’s possible at least in principle that perhaps one of these doesn’t actually hold. The underlying premise is really the laws of gravity, meaning Einstein’s equations. If you start off with a distribution of energy-momentum that interacts (approx) only gravitationally, then it’s actually difficult to avoid solutions that metrically expand in some way. FLRW is by no means a unique thing, it’s just a particular example of a large number of such solutions. This is not just due to coordinate choices. Indeed. And you are correct - you need to pick some boundary conditions to solve the EFE, which in this case is the cosmological principle. But in GR, the choice of coordinate system has no physical consequences, so it’s not due to that. The coordinates are chosen such that they correspond to an observer co-moving with the medium; this seems to apply to Earth too, since we don’t observe anything different. We remain in our galaxy, which is part of a local cluster, which co-moves along with everything else. In physics you are always restricted by the set of available data - our task is to find a model that best fits this currently available data. If the data set changes, then sometimes the model needs to change too. There’s many possible objections to the Lambda-CDM model, but honestly, right now there’s nothing else that fits all available data better. Let’s just consider this a work in progress. Physics would be boring if all the last words had been spoken already.

I think we can all agree that killing is immoral. I don't follow the reasoning where killing a few is more moral than killing many. And if so, how many ? And I find it strange that you think someone like President H Truman shouldn't value 100 000 American lives more than 100 000 enemy combatants. That is his job; to defend people he cares about. Oh, and I got 'pissy' like this because MSC commented about my morality, or lack thereof, not to simply be provocative.

“Alternating current is an electric current that periodically reverses direction and changes its magnitude continuously with time, in contrast to direct current (DC), which flows only in one direction.” One way to view the neurons in the brain is as alternating current rather than direct current such that our mind would swing between both halves of the brain like a pendulum. For example some synapses in the brain are multi-polar with multiple dendrites. So the way we can close one eye and lose some of our conscious awareness of blackness on that eye while looking out the other eye might feel as if our mind’s eye mind was in one brain location with both eyes swapping like each eye were an alternating scope. The partial blackness on the winking eye can help your depth perception where if you rotate your head towards the winking side and look out the same corner then the blackness of phosphenes above your nose will stand out a centimetre forward. An irony of viewing out with only one eye is that you might think your locus of consciousness was behind the middle of that eye instead of behind your nose as if your visual cortex swapped to the same brain hemisphere as the open eye. With monocular creatures like horses it’s possible to think if the creature had no brain then shining light through one eye might go straight out the other eye as if light had been teleported between both eyes. That way parallax could be helped by tiny time differences between both eyes as if the brain could virtually wink between both eyes were we to look at an angle towards a light bulb. Our mind is somehow levitating between both sides of the visual cortex with the nerves from the left and right sides of each individual eye diverging in the optic tract towards the visual cortex. I was musing beside a horse a few days ago! If both of our human eyes acted like projectors towards the back of our skull then they might naturally superimpose into one image.

Anything really big is going to present serious problems - but on the other hand they are easiest to detect. Mostly the biggest ones have been identified - and cleared of suspicion. Getting precise course prediction from as far out as possible will be important - identifying one aimed in the vicinity of Earth will include near misses too until it gets closer and you better not change it's course only to discover later that you've aimed it more closely rather than deflecting it away. I don't know to what extent changing albedo can be useful - spreading black soot over part of a comet could trigger more outgassing, or white coating to reduce it. For the stony and metallic objects, no. Any "light sail" effect is probably going to be extremely small. I think any gravity effect from a spacecraft will be extremely small too; if we can move enough mass to the vicinity to change it's course it seems to me we will be better usign that capability directly to move the mass of the object. Not convinced the net idea is any help - keeping impulses, however made, below the threshold for breaking loose "rubble pile" types apart seems better. Unless they are small enough that breaking them apart is a viable option - larger ones being less likely to be rubble piles in the first place.

I am curious as to why you think the ethics of nukes or other WMD would not be pertinent to politics and "devolve" a thread. I would be shocked by your assertion that city-annihilating nukes are okay for defending your loved ones, but I know you like being provocative, so I'm not. Seriously, do you really think a weapon that could destroy all or most of human life on the planet and turn vast areas into radioactive wastelands is a reasonable sort of defense for your preferred group? (Geordie has underscored the practical problem) How long do you think we would all last if everyone embraced this view?

\.begin{array}{rcl} a&b&c\\a&b&c\\a&b&c\end{array} \begin{array}{rcl} a&b&c\\a&b&c\\a&b&c\end{array} interesting the \begin{array} self activates f(z) = \left\{ \.begin{array}{rcl} a&b&c\\a&b&c\\a&b&c\end{array} \right . \[f(z) = \left\{ \begin{array}{rcl} a&b&c\\a&b&c\\a&b&c\end{array} \right .\]

Show how to get a conformal map from the region outside a semicircle, C∖SR={(x1,x2):|x1|2+|x2|2=R2,x2≤0} to the region outside a disk D of radius R2–√ centered at the origin, C∖D , ending up with h(u)=iR+u+i⋅R2−u2−−−−−−−√2 , with u=x1+ix2 . I know that the idea is to use a Moebius transform to send the semicircle to two perpendicular lines through the origin (something like az+Rz−R ) keeping track where infinity goes, then compress the three quarters we get the outside sent too to a half plane (again keeping track of infinity), then send that to the unit circle with infinity to 0 and then invert with z→c/z to get the outside circle of right radius and send infinity back to itself, but I didn't manage to get the correct result. Could you help me?

\[\vec{v}_e+p\longrightarrow n+e^+\] \[\array{ n_e \searrow&&\nearrow n \\&\leadsto &\\p \nearrow && \searrow e^2}\]

Because ,with nuclear weapons you cannot kill your opponent without also killing yourself and anyone you care about first(or in the hours to follow) The lucky ones will be those who are killed off most quickly. Morality meets expediency

This thread has devolved into an argument about 'morality', and 'mine is better than yours'. I don't need to justify my morality to anyone on a science forum; people dying are people dying, and and my morality says if you can save those you care about, you do what you need, up to and including nuclear weapons. Nuclear weapons are simply a better more efficient weapon for killing. So were knives and swords to people with sticks; did anyone complain about the morality of using them ? So were bows and arrows to people using knives; who complained about the morality of their use ? The same for guns, tanks and bomber planes.; why is it all of a sudden about 'morality' ? And why is it more moral to kill someone( or many ) with guns, or bombs, but not nuclear weapons, @MSC

Black Holes have entropy, and therefore, temperature, This temperature is inversely proportional to its size. A solar mass Black Hole has a temperature 60 Billionths of a degree K. All other Black Holes are even colder. That means almost all Black Holes larger than a solar mass are net absorbers of mass/energy ( the CMB is at 2.7O K ) I would think that this Black Hole involved in the collision is a relatively 'new' Black Hole that hasn't been very 'active' ( injesting mass/energy ). Maybe Mordred can shed some light on this; I believe it's in his 'back yard'. As Black Holes evaporate they get smaller and hotter, and radiate copious amounts of energetic radiation ( possibly encoding information ? ) before they lose their Event Horizon and explode back into normal space-time. This can only happen far in the future when the universe has cooled enough for stellar Black Holes to be net emitters of radiation, or, if primordial microscopic Black Holes ( formed in the high energy densities shortly after the Big Bang ) are reaching the end of their lives, None have ever been detected. My thinking has aklways been that no paticle can be constrained to a point, because that would imply ( By the Heisenberg Uncertainty Principle ) that its momentum ( and speed ) could be infinite, and it could escape the Black Hole. So I, and most people don't believe a central singularity is possible; it simply means our theory ( GR ) is not applicable at these energies and scales. I suppose this depends on your definition of 'theory' and 'hypothesis', but the theory does make some testable predictions.

your welcome glad to help

Uhu.. even a layman in physics may sufficiently grasp somewhat of the Higgs mechanism with fair and relevant instructions. Thanks.

Correct now your getting it +1 on seeing that connection

I'm further taking deal of. The Fermi constant plays a crucial role in describing weak interactions. (W and Z boson actions.) Where electroweak force and the Higgs mechanism are intimately connected within the framework of the Standard Model. As shown in the formula of the VeV's effecive_action, presented here earlier. Therefore the Fermi-constant incorporates into this formula.

It's a workable descriptive not completely accurate but sufficient for a layman understanding. Getting into the renormalization aspects would be a bit too advanced it's sufficient to accept that it's a renormalized value.

Concerning the VeV ("constant"), can one define this 246 GeV amount as some type of needed minimum "transition" energy when particles are about to acquire its intrinsic mass? (Probably not that simple, but in an elementary manner?)

Well at least Chatgp got that part correct as that's precisely what it's used for. The VeV is used in a similar manner just an fyi

Hmm.. yeah, right. Somewhat above my novel understanding. The Fermi-constant should be used in calculations involving decay rates, cross-sections, and other properties related to weak interactions. (Is what ChatGPT informs.) It was proven right in the finding of Higgs boson. I.e. the Fermi-constant was also more or less proven at the success of the LHC in 2012? (Besides the Higgs theory.) Much more to learn about such subjects. /chron44

If black holes slowly loss mass over time; is there a point where they stop being black holes and devolve into something more like a neutron star? https://news.ubc.ca/2024/04/05/new-gravitational-wave-signal-neutron-stars-and-black-holes/#:~:text=The 'mass gap'%2C spanning,theory than an empty gap. If so; would that explain the potential existence of objects falling within the mass gap between small black holes and neutrons stars? Objects that may have been detected in gravitational wave data? Incredibly old ex-black holes? Dying Holes. If there is a singularity at the center of a black hole, a point of near infinite density, would that same point also be a point of near infinite pressure? All that mass trying to explode outward while the gravitational force of itself keeps everything packed in. Extra question; is the idea a theory or a hypothesis? Explain that one like I'm 5.

Here is the association of VeV to Fermi-constant Fermi's interaction - Wikipedia

Extremely interesting, thanks for posting this. It seems this may shed some light on very early evolutionary processes by which other organelles may have arisen, by being first endosymbionts and then getting integrated into the cell. I know next to nothing about this but I presume a key feature of the change would be the progressive migration of at least parts of the genetic coding needed for replication, from the endosymbiont to the nucleus of the host cell. I think I have read this is thought to have happened with mitochondria, which still retain some of their own DNA, separate from the cell nucleus. I see this work says that the template for some of the proteins the former endosymbiont needs is now in the cell nucleus, but a label is attached to them which gets them picked up by the "nitroplast". Perhaps investigation of this will help us understand how eukaryotes acquired other organelles in the long distant past.

A marine algae and a nitrogen fixing bacteria have officially teamed up and the bacteria has become a new organelle inside a marine algae. The teaming up of nitrogen fixing bacteria and plants Is not a new (Azolla carolinensis) is one but the bacteria is just in a communal relationship with the plant but this bacteria has actually become an organelle inside the algae cells much like mitochondria or chloroplasts in other cells, this new organelle has been dubbed Nitroplast. https://newscenter.lbl.gov/2024/04/17/scientists-discover-first-nitrogen-fixing-organelle/ I am remembering reading of another animal that has evolved something similar that allowed it live in anoxic water in the black sea. If I remember correctly it was a ctenophore, anyone remember this?