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  2. An electroweak nuclear interaction between an anti-neutrino and a proton, producing a positively charged boson, resulting in a neutron and a positron. [math]\vec{\nu}_e + p^+ \overset{W^+}{\longrightarrow} n^0 + e^+[/math] [math]\;[/math] [math]\array{\vec{\nu}_e \searrow && \nearrow n^0 \\ & \overset{W^+}{\leadsto} & \\ p^+ \nearrow && \searrow e^+}[/math] Any discussions and/or peer reviews about this specific topic thread? Reference: Wikipedia - Electroweak Interaction: https://en.wikipedia.org/wiki/Electroweak_interaction
  3. Orion1

    test

    [math]\vec{\nu}_e + p^+ \overset{W^+}{\longrightarrow} n^0 + e^+[/math] [math]\;[/math] [math]\array{\vec{\nu}_e \searrow && \nearrow n^0 \\ & \overset{W^+}{\leadsto} & \\ p^+ \nearrow && \searrow e^+}[/math]
  4. Indeed, the thread of the sword is in less and less hands, so each pluck maybe the final straw; kind of a zeno's paradox... Do they have too???
  5. This what ChatGPT informs about Higgs field and its VeV: "The VEV of the Higgs field is fixed at approximately 246 GeV in the vacuum state, providing masses to particles that interact with it. Fluctuations in the Higgs field, if present, would generally occur around this fixed VEV, rather than changing the VEV itself. These fluctuations play a role in various quantum field theory phenomena but do not typically alter the fundamental properties of the Higgs field, such as its VEV." So, to my understanding: Higgs field and "its" VeV is merely or mostly a field which applies mass. No more essential physical stances or functions can be connected to this field? Though if this is the situation, this function in physics must be seen for very fundamental. Right?
  6. I suppose if there were a full stop after “human” and “believes” were rewritten as “beliefs” it could be rendered partly intelligible. But the bit about faith and believes [sic] still doesn't seem to make a lot of sense in the context of the rest. Can you paraphrase it for my benefit, or get AI to do so?
  7. Today
  8. We're never going to stop competing like animal's, but I think we may have come closest when some religion's started; Nietzsche's Übermensch perhaps...
  9. Blackholes could exist at the time of the CMB but the blackbody temperature Migl mentioned would still be far lower than the blackbody temperature at that same time period. So they would be growing and not dying. We really do not know what occurs beyond the Event horizon so any statement made would be nothing more than guess work There has been some research papers suggesting this as one possibility. They have even developed tests for this possibility. One of those tests directly relates to the article you posted concerning GW wave data.
  10. I put his statement into Deepl AI (the equivalent of Google Translate) and I don't see anything incomprehensible.. Except that zombification has many meanings, so the Collins dictionary will help you: https://www.collinsdictionary.com/dictionary/english/zombification ps. Personally, I would use "stupidification" instead of "zombification".. ps2. The majority of the population has no clue how computers, cell phones, internet, etc. etc. work..
  11. Let's explore a world where America didn't drop the bomb on Japan (assuming the secret was kept); would Russia bother to invest so heavily in developing such a bomb in peacetime, with their obvious strength in Europe? Korea would still be a radioactive waistland now, is that more or less suffering? That fact that they did drop it when they did took the weapon and it's devastating power, from the abstract into the reality. An abstract threat isn't really a threat at all politically, therefore no value as a deterrent. If we all have a gun to our head and no one is willing to pull the trigger, what's the point of trying to think of a way to uninvent the gun? Bc it's way easier to invent a way to deflect a bullet, than to erase all trace of knowledge on the subject.
  12. ! Moderator Note No optics, and chock full of unsubstantiated musings. The opposite of what I said. Don’t bring this up again.
  13. What about those regions where the CMB isn't evenly distributed? Could Dying black holes exist earlier in these places? In what state will the leftover matter contained within the black hole be after this Black Nova? Will this event kickstart the creation of a new generation of stars? Yeah I've always had a problem with the singularity explanation just not enough mathematical ability to ever be able to explain why, just feels wrong based on what I I've been taught of physics. I'd imagine there are a number of different theories and hyopotheses around the core state of a black hole beyond the event horizon. Maybe they are just really big neutron stars cloaked in the event horizon.
  14. I don't think that information access will be the issue of the future. It is the declining ability of folks to use it.
  15. 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?
  16. 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.
  17. 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.
  18. “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.
  19. 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.
  20. 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?
  21. Yesterday
  22. Mordred

    test

    \.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 . \[f(z) = \left\{ \begin{array}{rcl} a&b&c\\a&b&c\\a&b&c\end{array} \right .\]
  23. 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?
  24. \[\vec{v}_e+p\longrightarrow n+e^+\] \[\array{ n_e \searrow&&\nearrow n \\&\leadsto &\\p \nearrow && \searrow e^2}\]
  25. 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
  26. 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
  27. 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.
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