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  2. You've brought up a fascinating point about the complexity of ecosystems! You're absolutely right that traditionally, plants are considered producers and animals are considered consumers in the food chain. However, there are indeed instances where certain organisms blur these lines by exhibiting both producer and consumer behaviors. Plants like the Venus Fly Trap and other carnivorous plants are excellent examples of this phenomenon. While they primarily generate energy through photosynthesis like typical producers, they also supplement their nutrient intake by consuming insects. This unique adaptation allows them to thrive in environments where nutrient availability might be limited. In such cases, these plants can indeed be considered both producers and consumers. Their ability to generate energy through photosynthesis while also directly obtaining nutrients from other organisms challenges our traditional understanding of ecosystem dynamics, highlighting the intricate relationships between different life forms. It's moments like these that remind us of the richness and diversity of life on our planet, and how nature continually surprises us with its ingenuity. Thanks for sparking such an interesting discussion!
  3. Today
  4. If an undone fly was enough to let my junk burst out of my underwear and hang there in front of everybody, I think I'd be proud as opposed to embarrassed.
  5. Cosmological Principle implies \[d\tau^2=g_{\mu\nu}dx^\mu dx^\nu=dt^2-a^2t{\frac{dr^2}{1-kr^2}+r^2d\theta^2+r^2\sin^2\theta d\varphi^2}\] the Freidmann equations read \[(\frac{\dot{a}}{a})^2+\frac{k}{a^2}=\frac{8\pi G}{3}\rho\] for \[\rho=\sum^i\rho_i=\rho_m+\rho_{rad}+\rho_\Lambda\] \[2\frac{\ddot{a}}{a}+(\frac{\dot{a}}{a})^2+\frac{k}{a^2}=-8\pi Gp\] for \[p=\sum^ip_i=P_{rad}+p_\Lambda\] with conservation of the energy momentum stress tensor \[T^{\mu\nu}_\nu=0\] \[\dot{p}a^3=\frac{d}{dt}[a^3(\rho+p)]\Rightarrow \frac{d}{dt}(\rho a^3)=-p\frac{d}{dt}a^3\] \[p=\omega\rho\] given w=0 \(\rho\propto a^{-3}\) for matter, radiation P=1/3 \(\rho\propto{-3}\), Lambda w=-1.\(p=-\rho\) for k=0 \[H_o^2=\frac{k}a^2_O=\frac{8\pi G}{3}(\rho^0+\rho_{rad}^0\\rho_\Lambda)\] dividing by \(H^2_0\) and \(P^0_{crit}=\frac{3H^2_0}{8\pi G}\) gives \[1=-\frac{k}{h_0^2a^2_0}+\Omega^o_m+\Omega^0_{rad}=\Omega^0_\Lambda\] \[\Omega_k^0=-\frac{k}{h^2_0a^2_0}\Rightarrow 1=\Omega_k^0+\Omega^0_{rad}+\Omega^0_\Lambda\] densities can be written as \[\rho_{rad}=\rho^0_{rad}(\frac{a_o}{a})^4=\frac{3}{8\pi G}H_0^2\Omega^0_{rad}(\frac{a_o}{a})^4\] \[\Omega_m=\rho^0_m(\frac{a_o}{a})^3=\frac{3}{8\pi G}H_0^2\Omega^0_{rad}(\frac{a_o}{a})^3\] \[\rho_\Lambda=\rho_\Lambda^0=\frac{3}{8\pi G}H_o^2\Omega^0_\Lambda\] \[-\frac{k}{a^2}=\overbrace{-\frac{k}{a^2_0H_o^2}}^{\Omega^0_k}H^2_0(\frac{a_o}{a})^2\] with \(1+z=\frac{a_0}{a}\) densities according to scale factor as functions of redshift. \[\rho_{rad}=\frac{3}{8\pi g}H^2_o\Omega^0_{rad}(\frac{a_o}{a}^4=\frac{3}{8\pi G}H^2_0\Omega^0_{rad}(1+z)^4\] \[\rho_m=\frac{3}{8\pi g}H^2_o\Omega^0_m(\frac{a_o}{a}^3=\frac{3}{8\pi G}H^2_0\Omega^0_m(1+z)^3\] \[\rho_\Lambda=\frac{3}{8\pi G}H_0^2\Omega^0_\Lambda\] \[H^2=H_o^2[\Omega^2_{rad}(1+z)^4+\Omega_m^0(1+z)^3+\Omega_k^0(1+z)^2+\Omega_\Lambda^0]\] the Hubble parameter can be written as \[H=\frac{d}{dt}ln(\frac{a(t)}{a_0}=\frac{d}{dt}ln(\frac{1}{1+z})=\frac{-1}{1+z}\frac{dz}{dt}\] look back time given as \[t=\int^{t(a)}_0\frac{d\acute{a}}{\acute{\dot{a}}}\] \[\frac{dt}{dz}=H_0^{-1}\frac{-1}{1+z}\frac{1}{[\Omega_{rad}(1+z^4)+\Omega^0_m(1=z0^3+\Omega^0_k(1+z)^2+\Omega_\Lambda^0]^{1/2}}\] \[t_0-t=h_1\int^z_0\frac{\acute{dz}}{(1+\acute{z})[\Omega^0_{rad}(1+\acute{z})^4+\Omega^0_m(1+\acute{z})^3=\Omega^0_k(1+\acute{z})^2+\Omega^0_\Lambda]^{1/2}}\]
  6. Soooo ... You don't feel embarrassed, or awkward, at all, if your fly is undone, and your junk is hanging out, in a social situation ? Pretty 'ballsy' !
  7. It seems that while everyone in your ideal democracy is equal, some seem to be more equal than others. Unfortunately you are moving us back to the democracy of the 1700s, when democracy was more democratic if you happened to be a white, rich, male landowner. With your model you can be a female of color but you'd better have enough money for a computer and internet access.
  8. No that's not what I'm stating. The time reversal for anti particles results from the negative frequency modes. It doesn't mean the antiparticle travels back in time. That particular model suggested it did. One detail though electroweak symmetry breaking isn't really about CPT. That's more relation to baryogenesis and leptogenesis. Electroweak symmetry breaking describes when particles acquire mass and lose symmetry with other particles aka drops out of thermo equilibrium. This corresponds to the relevant force couplings. Strong, weak and EM force couplings. ( yes this includes Higgs Dirac and Yukawa couplings of the SM model). There's two very similar named processes that can get confused (Electroweak Baryogenesis) and (electroweak phase transition). The latter is the thermal equilibrium dropout. The former is suggested to occur during the EWPT (electroweak phase transition) happens. The (EWBG) electroweak baryogenesis is where the CPT relations are involved. Leptogenesis would occur just prior to EWBG. Once again involves CPT.
  9. Strange? In that it didn’t fit your preconceptions? It’s why we try and deal in facts, and want sources of information, rather than assertions about what one “feels” is the case.
  10. The possibility to initiate a referendum is not a "power" in common sense. For initiating a referendum, simply a sufficient number of "likes" must be gathered (and not too many "dislikes"), so many people like celebs or bloggers will be able to use that. Ok, I didn't know that. But strange.
  11. I'm struggling a little to recollect beer mediated musings from 30-odd years ago, so please bear with me. Am I correct in understanding your last point as CPT symmetry reversal is not a physically realisable phase change in contrast to say electroweak symmetry breaking or recombination?
  12. Yesterday
  13. Yes it's plausible the model I just mentioned had the same BB origin point. Matter and forward time in one universe. Antimatter and reverse time in the other universe. Both resulting from the same BB event. However as stated that model essentially died though you do come across attempts to renew the model. Here is a brief description of the model https://physicsworld.com/a/our-universe-has-antimatter-partner-on-the-other-side-of-the-big-bang-say-physicists/
  14. 1s it considered at all plausible that two ( more?) universes could be created from a shared event? Or is that just "intellectual incontinence"
  15. Rather meaningless to describe time as diluting. How one measures time is observer dependant. However you do not get time dilation due to expansion.
  16. I wonder ,does the Planck unit of time also dilate along with spacetime curvature(under extreme conditions, of course)?
  17. There was an older multiverse model that has matter in one universe with antimatter and time reversal in the other universe. It long ago fell out of any research interest. ( due to better understanding of anti-matter in that the time reversal is a mathematical treatment for symmetry purposes and not actuality)
  18. Probably the wrong word to choose. 'Pointlike' may be better. Suggesting that an instantaneous 'now' of zero duration doesn't exist. So a unit of Planck time, say, wouldn't have any clearly definable start or endpoint.
  19. Assumption from another thread that you aim for computational models running on currently available computer hardware; Any thoughts on how to get the resources needed to develop and run? Current state of the art machine learning requires quite a lot. Some old numbers from 2020; note that this supercomputer has not resulted in anything resembling AGI as far as I can tell: Reference https://news.microsoft.com/source/features/ai/openai-azure-supercomputer/#:~:text=The supercomputer developed for OpenAI,the top five%2C Microsoft says. That said, running a simple generative AI based software that generates text can be done on a consumer computer. It has nothing to do with developing intelligence but is useful in some contexts.
  20. It's a normal side-effect of being social beings. We generally wish for the approval and respect of our fellow humans - especially our superiors, peers and potential mates. Parents want their children to be successful in work, social situations and love, so they train their children in the niceties of their culture - its mores, manners, public demeanour, polite discourse, courtesy and protocol. People who can't or choose not to behave 'properly' are not well liked; other people don't want to marry them, be their friend, work with them, help them or support their ambitions. If you fail in or reject the major protocols, you become an outcast. In the more trivial aspects of public demeanour, people just laugh at you or frown at you. Farting in company is embarrassing. Dribbling sauce on your shirt when you're on a date is embarrassing. Showing up in a lumberjack shirt for a wedding reception is embarrassing. Simply because these things show you as incompetent or ignorant or just plain rude, and we don't like to be seen as those things. As for one's preference in clothing, we're a lot more liberal than we used to be. There have been times when the way a person presented himself - or worse, herself - in public could be viewed as a crime or breach of religious tenets. Wearing clothing intended for another gender can be considered in some segments of society a breach of decency. Wearing something outdated or inappropriate to the venue is not a breach of anything but aesthetic taste or fashion. Wearing something that doesn't suit you is nothing more that a disservice to your own attractiveness. Other people may look, may even snicker, but they don't condemn you.
  21. That was your lead sentence. You had not posted prior to that post. What followed was “as for the rest of your question” So no, there was no context that’s missing. So…today? Condolences. Why should celebrities have more rights and power than the average person. Surely that’s more like an oligarchy than a democracy. Evidence that this is the case? the US is currently pumping more oil than ever, and we have a dem president. “United States produces more crude oil than any country, ever” https://www.eia.gov/todayinenergy/detail.php?id=61545 Production rose dramatically between 2009-2016, when a dem was president, after having dropped under the previous repub president https://www.macrotrends.net/2562/us-crude-oil-production-historical-chart But that opens us up to the tyranny of the majority. Why should people far away have a say in something that might pollute your back yard?
  22. I didn't know there was absolute time at any scale. For a t=0 in the context of the earliest part of the universe what reference frame is chosen for t to apply to? Any frame that is not actually specified as "the beginning"?(and as close as possible to it for "simplicity's" sake?)
  23. Good but it's still useful to understand how the NFW profile deals with Kepler curve. Now a little hint there is a means for a matter only universe to expand though it's related to gravity it isn't how it's described so far in this thread. Gravity only attracts it never repels. Matter also exerts no pressure term. So it isn't due to pressure.
  24. In my last post I didn't dispute the existence of the dark matter.
  25. More of a dual-universe speculation. Perhaps one way out of the t=0 conundrum is to drop the idea of absolute time at these scales in favour of a sequence of time intervals, one of which happens to span t=0. A form of quantisation if you will. The surface of that cell should have no associated infinities, but half of the boundary surface is time-reversed and that (the point you raise) would need to be addressed. It's probably complete tosh, but the idea of two universes being spawned in opposite time directions has a pleasing symmetry to me.
  26. Once again simply applying Newtons gravitational laws will tell you differently. The only way to avoid Kepler curve for rotation is to surround the galaxy with a fairly uniform mass density that is greater than the baryonic matter distribution. Aka dark matter via the NFW profile. We can also detect our motion and compensate this is called dipole anistropy it's actually why the first Planck dataset had the axis of evil. They didn't have the needed calibration for our peculiar motion.
  27. There's a BUNCH of people these days who believe in a vertical morality, where they position others on a scale of right/wrong with themselves as judge, using a hodge-podge of religious teachings and confirmation biases to determine whether they're worse or better than others. The best of them only judge your worst behaviors, but too many cast a broader net, trying to put you below them on the morality scale because of the music you listen to, or the way your hair looks, or the money they think you don't have. Humans brains naturally look for patterns. They give us conventions we use to assess situations in our lives, based on typical experiences. Historically, noticing things that diverged from typical patterns has saved lives and enriched many individuals. "A critical eye" is often applauded in many societies, and may embolden your parents to "fix" your broken biker look. Most parents secret unreasonable wish is that their kids not get picked on for any reason, that they fit in, and get along with everyone. And then some folks take it to extremes. They don't think of things as typical or divergent, they think of them as right or wrong. I think these folks need to realize how worthless and destructive this kind of judgement is. I had a friend once who wore wildly colorful clothes, and if anyone called him out for it, he just said, "If I look just like you, why do we need you?" Loved that guy.
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