Jump to content

Leaderboard

Popular Content

Showing content with the highest reputation on 07/25/20 in all areas

  1. I can't believe I'm defending an anti-evolution stance, but you're strawmanning their argument. The part they disagree with is natural selection leading to a change in species over time, not that traits are passed along without reproduction. You're making their argument too simple in order to discredit it, and that's using a fallacy to support your own argument. Most anti-evolution arguments acknowledge what they call "microevolution", where children share traits from their parents. They just don't believe natural selection can account for a complete change in species. Anybody who is looking only at their own life and reproduction isn't addressing evolutionary concerns. Natural selection is one way to change allele frequencies within a population over time.
    2 points
  2. This is actually not very difficult to conceive in principle within the quantum formalism. Quite more difficult is to give a precise and detailed answer. As Eise has told you, a quantum particle, in some sense, sniffs around all of space time. When you see it in a mathematical formula printed on a paper, you see very clearly it doesn't look like the whim of a god. It does look like a precise mathematical pattern of evolution. Now, this evolution, in a quantum theory that includes special relativity, is very puzzling, among other things, in that it includes modes of propagation that are superluminal, subluminal, every which way. Those are called "virtual amplitudes", and they appear in the calculations, although they cannot be measured. They are called "off-shell". The basic reason for this is actually a peculiarity of relativistic kinematics. A real photon satisfies a condition or reality that has the form, \[k^{2}=0\] k is called 4-momentum, and codifies the direction in space-time in which the photon is moving. It's a combination of 4 numbers, the time component and the 3 spacial components: \[k^{2}=\left(k^{t}\right)^{2}-\left(k^{x}\right)^{2}-\left(k^{y}\right)^{2}-\left(k^{z}\right)^{2}\] So it could be negative, positive, or zero in general. Real photons are null. For real photons this quantity must be zero. But you can always decompose this "real" state as made up by the real components plus many other virtual ones, \[k^{2}=\left(k+p\right)^{2}\] These virtual ones have momentum ("direction") p, which is not physical, and in particular could be superluminal or subluminal: \[p^{2}>0\] \[p^{2}<0\] as long as they give you a real photon: \[0=k^{2}+p^{2}+2kp\] I haven't shown you the full-fledged argument in quantum field theory, which goes with amplitudes and so-called Dyson time-ordered formula, but a simplified version of it. It is by no means a foolproof explanation. But here's my question for you: Can you guarantee that the positions where the particle can or cannot land (the not-so-well-known partial reflection paradox is another interesting example) are not set in advance by all the components of the quantum state, including the virtual ones, that make up the Feynman propagation formula?
    2 points
  3. Particle wave duality. I can’t remember where, book or video, probably video maybe both, but it was presented amazingly that a particle could pass through two slits at the same time. To me that would be amazing. So, I question it. It’s difficult for me to accept, as I understand the concept. Of course it could be my understanding. I read that for what seems the most part particles only exist for a short time. Also, amazingly presented as popping in and out of existence. Then there is my understanding of Heisenberg‘s uncertainty principle. Note, I am not questioning it. I am accepting it as true to a point, and that point is that you can’t measure both at the same time. To me that seems awkward if not amazing. So, I question it. Then there was the concept of ether. That was shown to be not true. I am not saying that it is, but the fact that it was shown to be not true seems amazing. No I’m not going to question it, except to ask that if the universe is full of continuous particles why was it so easily shown that the ether does not exist. Then there is solid to somewhat solid matter. Why do I exist? No, I am not asking a philosophical question. Why am I cohesive? Do all particles pop in and out of existence? I am aware that it doesn’t quite happen that way though I do not exactly understand how it does happen. In a sense I’m parroting another amazing rhetoric. I am however wondering given my somewhat limited understanding of quantum physics, if I am solid, or is anything else for that matter? My mind can be changed, even taught, but I am not going to simply accept what seems incomprehensible. So, I think about some apparently amazing presentations and think there must be some other explanation. With Heisenberg, the presentation, pick a book or video it really doesn’t matter, comes across as you can not measure both as related to an it. You can measure it’s momentum, you can measure it’s position, but when it comes down to (it) you can’t do both. Realistically, I accept particle wave duality, but have trouble accepting that a particle can travel through two slits at the same time, but I can accept that a wave can. I also understand from different diagrams that some don’t agree as to how a wave propagates. Which can really muddy up a thought. It seems to get more difficult, at least for me to mentally picture such thing, spherically. So, I prefer the presentation where you are looking down on presumably a wave capable medium that upon disruption attempts to propagate in the allowed directions. The produced wave/s go through both slits. I have trouble with analogies, but opposing waves can peak in various places. Like particles popping in and out of existence. The wave is an analogy of energy propagation through a/various fields of energy/energies. The medium, well for lack of a best definition, is simply vast. Back to Heisenberg and the inability to measure both of (it’s) momentum, or it’s position. I’m suggesting that is because it is not an it but rather two peaks created by the act of measuring. The wave peaks when it interacts with the measuring devices. In essence the wave peaks every time you take a measure. I don’t think the particle is amazingly going through both slits. What is seen is/are peaks of a propagating wave/s where it interacts with opposition. For a moment of time a particle is created and observed. Among other things the photon is not displaying a gravitational attraction or reaction to an intense gravitational field. The energy waves created by the distant star are going around. The observed photon does not exist until the wave/s interacts with the observer. I can’t think of any reason why these thoughts might be seen as an attempt to dismantle physics. To me they just seem to be a rational way for someone who is not an expert to grasp the reality of a few things often presented as amazing, but true! (Among other things the photon is not displaying a gravitational attraction or reaction to an intense gravitational field). This part I am still thinking about? I have another thought that requires gravity, that possibly comes from particles that pop in and out of existence due to opposing energy fields, but that is another thought.
    1 point
  4. ! Moderator Note You were told to stop
    1 point
  5. My first serious girlfriend would on occasion point out my unintentional tendency toward male chauvinism. With those memories in mind I am almost afraid to 😊 in what is likely be a mixed environment... Oh... what the hell! 😂😂😂
    1 point
  6. Somewhere near the centre of Jupiter (many factors might put it at other than the exact centre of mass) the pressure would hit a maximum. At that point the pressure gradient would be zero.
    1 point
  7. I agree there is a great deal of off topic discussion which makes it difficult for someone studying relativity from the beginning and for those trying to help that person (the OP). +1
    1 point
  8. While I was doing observation in the backyard I had recently found a small mushroom the stalk of the mushroom is very thin, is it interesting.The tahallus of the mushroom is white in colour and is slightly having heart shape
    1 point
  9. So all that is needed for your ship to be ready to fly is the invention of a working Bussard engine. And the invention of a working fusion reactor. And then the further invention of a working fusion reactor that can be miniaturized. And then the invention of artificial gravity. And then the invention of cryo-sleep. It doesn't seem like this is something we are going to be building in the near future.
    1 point
  10. Good point. But does it, really? I am not really sure I understand how you get from \(ds^2\) to a notion of event sequencing. Yes, this is essentially what I was attempting to get at - interpreting \(ds^2\) as time isn’t straightforward. I would agree to this, but like yourself I can’t at the moment put my finger onto just why that is. What’s more, I think our concept of “space” is actually equally problematic, albeit in more subtle ways. My - entirely unscientific - intuition is that neither one is really fundamental to the world, which is why I was speculating about other options over on the other thread. Precisely - all our formal systems (languages, maths, computer code etc) are in some way sequential, because all our mental processes are. We think, feel, and reason in linear 1-dimensional ways; we can’t do anything else, because that is how our minds are structured. For me, that may (!) suggest that our models of reality (both our mental representation of the world, and our abstract descriptions of it) simply inherit that structure. In other words, this may (!) suggest that we use ‘space’ and ‘time’ in our models not because they are actual features of the world, but because that’s how our mind (the originator of those models) is structured. So the question is, can we separate the physically relevant structures within our models (i.e. the parts that encapsulate the actual physics) from their spatiotemporal embedding? I have a feeling that we might be able to, which would have pivotal consequences for the ontological status of space and time. For example in QFT, what is the actual fundamental ontology of that framework? I don’t think it’s momentum eigenstates, or any of the operators in themselves, or the S-matrix, or even the concept of ‘particle’ - it seems we need to rather look at the commutator algebras and symmetry structures that underlie them. Which are not spatiotemporal concepts in themselves. When we play around with embeddings in different spacetimes, we then find all kinds of interesting things, like the observer dependence of vacuum states etc. This raises serious philosophical questions about space and time. I’m just think aloud here Wick’s theorem?
    1 point
  11. Leonardo DiCaprio is much more. He is my climate change ambassador: https://www.climatechangenews.com/2014/09/17/leonardo-dicaprio-appointed-un-climate-ambassador/ Actor just play a role..
    1 point
  12. Debt is an extremely powerful tool, but like all tools it must be wielded intelligently and with a clear understanding of risks. The entrepreneur who scales her manufacturing to meet the demand when it hits, but does so through a loan. The parent who lives rurally, but acquires s better paying job in the city in order to send their children to a better school and achieve a better future for them, but who can only do so by taking out a loan on a car. The person who takes a mortgage on a house to live in an area with more benefits and better schools, and who with each payment on that mortgage contributes to their own future equity. Or the craftsman who borrows to buy materials to build a product they can sell at 4-10x the input costs, or the street food vendor who borrows for her ingredients or the plates to serve her customers upon... customers who help her earn several multiples of what she initially went into debt to acquire. Like any tool, debt used wisely is a powerful path to escape poverty and build a better tomorrow. Microlending programs across the planet demonstrate the validity of this point every single day and they have for decades. Also just like any tool, debt in the hands of those who use it ignorantly or with abandon is a risk that comes with real and fairly predictable long-term consequences. Unfortunately, idontcare, the only tool here seems to be you, with your sweeping generalizations and desire to preach instead of discuss. It’s okay that you’re not a fan of debt, but you’re failing miserably to recruit others to your perspective. I’m sympathetic to your core point about the risks of debt and how so many millions (even billions) on our planet are harmed by it... and how many are everyday harmed by cronies who wield the power of debt and credit like a weapon upon the masses... but unfortunately you squander that sympathy and evaporate my patience with your continued soap boxing and closed mindedness. It seems you’d rather scream into an abyss and rake muck than to partner with others to explore potential solutions or improvements... and AFAIC you may just as well toss yourself straight into that endless void and never come out if you choose to persist in displaying this lack of interest in being better or trying harder to be a rational and reasonable discussion participant.
    1 point
  13. Don't borrow and you'll never be a slave to debt. If, on the other hand, you're greedy, and you want a nice house, a nice car, the latest iPhone, the best schools for your kids, and two vacations a year, go ahead and borrow. Lenders are only too glad to have you pay interest. But don't be confused. You're not a slave to debt, but to your own greed.
    1 point
  14. There is no such thing as absolute "motionlessness" to achieve. The Solar system orbits relative to the center of galaxy. we can give its speed relative to this center. The Earth orbits relative to the Sun. Our galaxy has a velocity relative to the center of gravity of the local group. The local group has a relative velocity larger galactic cluster it is a part of... But none of these motions are with respect to some absolute state of "rest", as no such state exists, and it is meaningless to talk about one. You can only consider velocities as being measured relative to some reference. And any reference you chose is just as valid as any other. Thus you are free to choose whichever one is the most convenient to work from. If the one where you consider yourself or anything else as being at rest is best for your purposes, you are free to use it. If you have a velocity of 100 mph relative to me, it is the same as I having a 100 mph velocity relative to you, and that is as far as it can go. There is no absolute rest frame that either or both of us are "really" moving with respect to.
    1 point
  15. Not a very useful line of thinking for homework help.
    1 point
  16. Are you suggesting beta decay is playing a role in conscience?
    1 point
  17. Instead of doing science, let's see what the highest number the average Murrciann can count to and make that the price for everything. Grow the fuck up, I won't participate in this idiocracy
    0 points
  18. Why do you think it was a bad movie? I liked it... Character played by Leonardo DiCaprio says about 50% commission from penny stocks trading.. As a somebody who has years of experience in stocks.. here we have stockbroker's commission less than 2% even if you order stocks by phone. With on-line trading it can go very low, to less than 0.25% the last time I purchased stocks (when you're doing day-trading i.e. buy and sell in the same day). Movie presents past times '90 or so.. I even wrote application (actually two) for calculation stockbroker's commission (it is added during buying and during selling, with minimum on the both), to tell me when stocks will be worth selling (i.e. enter amount and stock price, output with commission, enter current price, output with commission, calculate final-sell-price minus final-buy-price) People/companies with high volume (i.e. VIP) can negotiate custom stockbroker's commission fee.. This movie is about how salesman of whatever can manipulate weak mind people..... Now you have POTUS-world-gun-salesman/peddler... Peddler with airplane. ... in that statement you are right ... most people only think of money, how to get it, etc etc. etc.
    0 points
  19. Let's consider that stupid rule instead of true science because it will appear again and again . (Pi/million)*million=Pi (Pi/billion)*billion=Pi There is no trend to reduce result therefore so called scientists should prove that billion is not nearer to infinity than million.
    -1 points
  20. Universe will contract, time must reverse I will prove with geometry why the universe must contract one day. As the universe expands, the time frame within the funnel like universe expands causing the boundary of the funnel like universe to reach towards 180 degrees. At that point the time frames cannot not expand any further. Because a universe cannot remain still in expansion and expansion is no longer possible, the universe will revert to contraction towards the singularity. My reverse order mathematics is confirmed. Like all physics equations using my reverse order math, time will reverse order leading to an opposite and equal reaction enforced by a God like entity.
    -1 points
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.