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MarkE

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Everything posted by MarkE

  1. I'm referring to the zero-energy Universe, which states that that matter (positive) is cancelled out by gravitational attraction (negative). Furthermore, the observations support it. There is a constant in the Friedmann–Lemaître–Robertson–Walker metric that determines whether the Universe is curved and infinite, curved and finite, or flat. The energy densities for those three curvature cases are +, - and 0. General relativity isn't valid at Planck time, or when the density of the Universe is greater than the Planck density. That needs quantum gravity (which we don't have). Extrapolation back to conditions like the Planck units is not legitimate.
  2. We live in a flat Universe in which the value of the combined energy is 1, and that of gravity is 1. The law of conservation of energy states that energy can only change in form, never increase its amount. So if all of the energy during the beginning of the Big Bang had the value of 1, that same energetic value applies to the Universe we have right now, even though there are lots of particles around. All the particles of the Universe together still make up that initial value of 1, so the composition of the distribution of energy in the Universe has changed, and is continuously changing, but the energy value itself can’t change. So you can’t add anything, only divide what you already have. Taken this in account, it has been proposed by Edward P. Tryon that the Universe may be a large-scale quantum-mechanical vacuum fluctuation, where positive mass-energy is balanced by negative gravitational potential energy, a reference to measurements that indicate that we’re living indeed in a flat Universe. The inflation theory, which came later, was able to explain how our Universe could inflate from a tiny particle. Before fermions, there must have been bosons, matter before energy. Why? Well, if you start off with a hot Universe, and you let it cool down, you’ll predict that you wind up with about 74% hydrogen and about 24% helium by mass, which is the initial composition of every star. Our sun right now consists of about 62% helium (because it's about 5 billion years old), but initially this was 24%. And all elements, except hydrogen and helium, are made in a star. If the Big Bang were to generate the right amount of helium and other light nuclei, then there must have been an era in the early history of our Universe in which light, not matter, made up most of the energy. That being said, what I still don’t fully grasp is, if this is indeed the explanation of how our Universe came into being, and photons could have pair produced into + and – particles, then how did these newly created matter/antimatter particles further divide (because ‘adding’ energy is not allowed), and give rise to other particles, which lead to this Universe that is filled with photons and matter/antimatter particles? They couldn’t, of course, because, as Sensei clearly remarked: Photons are able to divide (pair produce), but electrons/positrons can't. If these matter/antimatter particles could only undergo change by annihilating with each other to form photons again, then this process could only have taken place back and forth, and this could never have yielded the Universe we live in today. Therefore there must be something else going on than just ‘quantum fluctuations’, and photons that turn into matter/antimatter particles, because the initial particles that made up the early Universe couldn’t just change form by dividing themselves further and further.
  3. I really would like to understand all of this, so I hope you don’t mind me bringing earlier discussions up again. You’re saying that the first RNA cell doesn’t necessarily have to be a virus. But what’s the other option? Earlier, you wrote “most evidence point to a prokaryotic origin of the nucleus”, but a prokaryote is already a very complex cell. Before a strand of DNA, there must have been a strand of RNA first (just like the modern virions) which, at some point, must have encapsulated itself with, or hijacked, a (self-assembling) lipid bilayer as a membrane. Isn't the least complex cell type that of a virus? You're referring to "one emerging view”, but I have a hard time visualising the fuelling mechanism you're describing. Could you provide any references to this (new?) emerging view, because it sounds very interesting. And thanks for explaining (again), by the way.
  4. Do you support the RNA world hypothesis? If so, isn't it more probable to suggest a viral ancestor first, and a bacterial/archaeal ancestor that came after, because only viruses can have RNA-based genomes, whereas all other life forms have DNA-based genomes? One of the problems with the RNA world hypothesis is to discover the pathway by which RNA became upgraded to the DNA system. While conducting a survey of viruses in a hot acidic lake, scientists uncovered evidence that a simple DNA virus had acquired a gene from a completely unrelated RNA-based virus. It is suggested that viruses are capable of converting an RNA-based gene into DNA and then incorporating it into a more complex DNA-based genome, some 4 billion years ago. This finding supports the argument for the transfer of information from the RNA world to the emerging DNA world before the emergence of the last common ancestor. From the research, the diversity of this virus world is still with us.
  5. Interesting topic! I was discussing the same subject with CharonY earlier (in this topic). If this hypothesis is correct, then this would mean that the remaining 57%, the "human" part, is not human at all, since the eukaryotic cell itself is made up from bacteria, archaea and yes, even viruses (our cell nucleus):
  6. That sounds interesting, I haven't heard of this study before. I'd like to learn more about this, could you provide any references/papers to this research?
  7. @CharonY, do you support the eukaryogenesis hypothesis, which states that the eukaryotic cell nucleus is derived from a virus? According to the viral eukaryogenesis hypothesis, the eukaryotic cell is a composite of three phylogenetically unrelated organisms: a viral lysogen that evolved into the nucleus, an archaeal cell that evolved into the eukaryotic cytoplasm, and an alpha-proteobacterium that evolved into the mitochondria. A lysogenic helical virus with a bilipid envelope (such as the pox virus) bears a distinct resemblance to a highly simplified cellular nucleus (i.e., a DNA chromosome encapsulated within a lipid membrane. What are your thoughts about this hypothesis?
  8. Once it's inside a host, a virion behaves in a way we associate with life. And didn't all life originate from a (virion-like) RNA molecule? There's also the knowledge that influenza viruses manipulate humans into behaving more sociable, and make us sneeze to spread the virus even further. Research has shown that endogenous retroviruses (that make up 8% of our genome) play a crucial role in the functioning of our brain. Among other things, hese viral sequences are able to regulate which genes are expressed. Mammalian cells have mechanisms to keep these genes silent by coating their DNA with molecules that suppress viral genes. However, despite this effort, the viral genes still manage to find a way to be switched on regardless. Scientists have discovered that in a multiple of different tumour cells, proteins had been produced by endogenous retroviruses. I'm not convinced that viruses aren't at all related to living organisms in any way. They can deliberately influence a host in their own advantage, so to state that this is just some kind of glitch in nature, collateral damage that is coincidentally caused, can't be the whole story. If we can't change the definition of a virus, or a gene, in our current classification system, then perhaps we have to redefine the definition of life.
  9. I would view viruses as pathogenic organisms. For instance, it's well known that helminths and protozoa (Toxoplasma Gondii, Dicrocoelium Dendriticum etc.) can manipulate their host by altering their behaviour. Bacteria in the gut are able to alter the neural signals in the vagus nerve. They can influence our decisions (what we eat) by releasing signalling molecules into our gut, and change our taste receptors. Well, a virus manipulates its host vector as well. I did a little bit of research on the web and found out that there's a virus from the family Baculoviridae infecting moth and butterfly caterpillars, that incites them to eat incessantly providing nutrients that are needed for the virus's replication. When the virions are ready to leave the host, the caterpillar climbs high into a tree (which they would normally avoid, due to the risk of predators), until its cells are made to secrete enzymes that dissolve the caterpillar (yes, dissolves ), and the virus drips down onto leaves, which will be consumed by new hosts. Therefore, I'm not sure if I can support your argument that viruses are merely genetic elements, rather than living organisms: Why aren't coding genes considered 'alive' anyway?
  10. LMGTFY. I was referring to ‘the universe’ , not to 'energy', thanks for pointing that out, and excuse for being grammatically not clear enough. Energy itself isn’t expanding, a particle can’t expand, particles can however divide (which was the main point I was trying to make), and because they divide, the space between those particles expands. A long time ago I’ve read this book called ’13 things that don’t make sense’. If I remember correctly, there was a quote in it that went something like “Dividing matter will generate less and less, but dividing energy will generate more and more”. I’ve always thought that this was an interesting idea. Maybe it’s true after all, even though it doesn't make sense.
  11. The huge universe we have right now, with lots of matter and energy in it, is not a consequence of increased energy, because energy is conserved. The fact that there is energy in the first place, and that it is expanding, means that once it must all have been located at 1 single point in space. This 1 point of energy could not increase or duplicate. This means that it was only able to divide into parts (I’m referring to all the particles in space). You could interpret the distribution of energy in space in an abstract way, in terms of numbers/values. The "stuff" in the universe basically represents this energy value of 1, but is divided into more and more parts. So that would generate particle values such as 0,0000000000000000000005 or something like that, probably even smaller, but my point is that all these particles together would still make up the initial energy value of 1. And gravity should have the value of 1 as well (-1 to be precise, because we live in a flat zero-energy universe in which all the matter is cancelled out by gravitational attraction). All energy together make up the value 1, and all gravity makes up the value of -1, which makes 0, and therefore a flat universe. Observations support the zero-energy universe idea, that matter (positive) is cancelled out by gravitational attraction (negative). There is a constant in the Friedmann–Lemaître–Robertson–Walker metric that determines whether the universe is curved and infinite, curved and finite, or flat. The energy densities for those three curvature cases are positive, negative, and zero.
  12. If black holes symbolise the male nature because they only take, how then would you interpret Hawking radiation (a black hole that is GIVING off radiation)?
  13. How do you call a piece of classical music composed for pedophiles? "Symphony in A minor".
  14. Interesting. Where/when? Also interesting! "Thermal fluctuations provide the energy necessary for the atoms to occasionally hop from one site to a neighboring one". Seems like some kind of quantum tunnelling.
  15. OK, so all of the above statements are correct? I didn’t make any wrong assumptions? One other question then: if entropy can sometimes be violated, what would be a good example of this happening here on Earth? When and where has it been observed?
  16. Good point. They're all called "laws", not a-law (absolute) versus r-law (relative), unlike the clear distinction between mRNA (messenger), tRNA (transfer) and ncRNA (noncoding).
  17. Entropy is a statistical law, an approximate conservation law. Shouldn’t therefore this “law” be added with ‘…most of the time’, instead of implying that it’s always the case, by using the term “law”? By introducing Maxwell’s demon, he visualised how this 2nd law of thermodynamics is about probability, an unlikeliness, a statistical impossibility, but not an absolute impossibility. Therefore violating the 2nd law is a statistical possibility, which can only be violated with a tiny probability, but on average entropy doesn't decrease (like throwing heads 1000 times in a row instead of tails). Emmy Noether discovered that with every conservation law there’s a symmetry involved. There’s for instance always a conservation of charge, a related principle to Maxwell’s equations. Since entropy is an approximate conservation law, entropy therefore shouldn’t be symmetrical, always and everywhere. I’ve always thought that Maxwell’s equations are beautiful and symmetrical, but I guess the only symmetry in these 4 equations can be found in the wave function of the photon itself (like all bosons, in contrast to the asymmetric wave function of a fermion), and not in the equations themselves. In this video (at 2:30 minutes) the lack of symmetry (between the 1st and the 2nd equation) is also mentioned. Am I making the right judgements and conclusions here?
  18. So the question is whether the genes in male sperm are actually turned on or off by methylation or not. "Some areas of the genome are methylated more heavily than others, and highly methylated areas tend to be less transcriptionally active, through a mechanism not fully understood. Methylation of cytosines can also persist from the germ line of one of the parents into the zygote, marking the chromosome as being inherited from one parent or the other (genomic imprinting)." Interesting, but that's not quite it. The direct connection between the external environment and the internal world is missing. The brain may observe the male-female ratio, but how is this translated to the germ line cells? It's known that bacteria in our gut are connected to the brain through the nervus vagus (and thereby are able to influence what we eat), but male sperm isn't connected to the brain the same way in order to send or receive direct messages (other than testosterone).
  19. Thanks for that! I've read one interesting thing (in your first URL), called 'Fisher’s principle'. It basically says that if there are more women than men, a newborn male would have better mating prospects than a newborn female. I think he has a point there, but it still doesn’t explain how this kind of information about the environment could have influenced the gametes. I guess the underlying chemical mechanism is still a mystery to science.
  20. @CharonY I guess we don't yet know the full story of gender determination, and why in most species both genders are on average in balance with each other, even though we're aware of the fact that food scarcity can be, in some cases, an indication of gender determination. In conclusion, I think it's interesting that it's surely not just the fastest swimming sperm/spore that determines gender.
  21. That's true. Does anybody know if this has ever been researched?
  22. In the article I've read two things that could explain the how and why of gender determination: "The Harvard-based pair theorized that as the physical condition of a female declines — if she’s nutritionally deprived, for example — she’ll tend to produce a lower ratio of male to female offspring. Evidence of the theory came from red deer and humans; in both species, adverse conditions in the mother’s environment during pregnancy are correlated with a shift toward female births". and: "The mechanism behind this finding, and what it takes to trigger this decline, however, are harder questions to answer. One study, Discover reports, found that males during pre-embryonic development have lower rates of survival than females when a mother’s blood sugar levels are down, so it could be that the selection pressure happens after conception". If this is indeed true, then there's no direct correlation between the womb/gametes and the external environment. It would als mean that @StringJunky was right after all. But I'm not yet convinced by this explanation, because how then would you explain the average 50-50 ratio birth rate of boys and girls in famine threatened African countries? Take the common reed frog, who can change from a female into a male, which likely occurs when the population does not have enough males to allow procreation. That's an example of the external environment that accounts for determining gender. The same thing has been observed in clownfish, when a female clownfish dies, a male will transform into a female (females are highest in dominance). So this is again an example of an external environmental cause, not the mother's metabolism. Yes, the mother's metabolism and hormone levels change, but this happens as a reaction to something else in the external environment. Of course, gender shift after birth is different from gender determination before birth, but a mother's internal milieu doesn't have to be the only explanation for human gender determination.
  23. I guess it's really true then, thanks! The question that still remains is how the fertilisation process is influenced by external conditions. How does the body actually know that there is food scarcity, and how is this translated to the gametes?
  24. Yes, but on what scientific grounds is this relation considered a correlation?
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