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  2. Okay I do what you ask because it off topic for that thread. Can you other here define what is science, bad science, junk science and pseudoscience. What makes good science and what makes bad science? To my understanding I always thought bad science or junk science did not have any science backing like saying you can walk on water, earth has no center mass or time travel.
  3. Is the Universe infinite?

    There is no evidence (or explanation) for the "creation" of the universe. If you mean, "how could the universe grow to be that big in that time" then I'm not sure what the problem is. Imagine that, at some point, the observable universe was 1mm across (and is now 96 B light-years across) then at that time, the whole universe would have been 150 times larger (150mm) and would now have grown to 14 trillion light years.
  4. What are you listening to right now?

    Nice song... I loved steppenwolf back in the day!
  5. Mass in black holes (split from Mass)

    This sums everything up. Do you people know and understand what an event horizon is? I'm posting science, you people post misinterpretations based on science yet you seem to think I'm posting subjective beliefs This discussion is not fair.
  6. You mean this? [a,b]? This is notation for commutation. It asks whether the process of multiplying in a binary way, two variables is commutative. The notation [a,b] is simply in this context, (ab-ba). Classically speaking, many things never commuted anyway. It wasn't just a special feature of quantum mechanics. When you do speak about commutation and Von Neumann algebra, you end up dealing in what we call the phase space.
  7. This is a good one for the long winter evenings ahead. But please indicate for the sake of those of us who don't do this all the time, the meaning of your bracket symbols.
  8. Is the Universe infinite?

    Thanks So now as we know that the Universe extends for at least 14 trillion light years in diameter - How can we explain a creation of that Universe size in only 13.8 BY? How the BBT fits to this size of Universe?
  9. Today
  10. One could argue that it is Gravitational potential which provides the unrelenting compression for the H and He nuclei. This compression gives temps and pressures at the Sun's center to fuse H ( and even He nuclei Studiot ) into heavier and heavier elements. When sufficient radiation pressure is produced by the various fusion reactions, the Sun 9 or any star ) is in equilibrium ( somewhat ) and will stay that way for millions or billions of years ( depending on its size and composition ). When heavier elements ( approaching atomic number 26 ) are produced by the fusion process, it is less and less efficient, and eventually n iron core results in a brown/white dwarf star. In the case where the star is really massive, the nova/supernova process injects energy back into the core ( also gravitational ) and produces heavier elements above iron ( atomic number greater than 26 ). The shock waves from the nova blasts also compress interstellar gases ( mostly H, various amounts of He, and heavier elements ) to create new stars. So you could say that, far from being the weakest force, Gravity is the one that makes everything happen.
  11. Is the Universe infinite?

    Thanks for putting that so succinctly. I was going to say more, but I thought it might end up getting into different types of infinity, the continuum hypothesis and so on!
  12. Smuggling Nuclear Weapons

    Not my field, but I understand there are many clues in the nuclear material as to where it originated. That won't tell you who built the bomb, but it's a good start.
  13. Abstract I explore the anticommutating spacetime relation in context of gravity by seeing commutation happen in two connections of the gravitational field, one concerned with space, the other time. We learn nothing revolutionary this time around, but we do explore it in a finite dimensional, Hilbert space-context. I do offer though, in a new context, an equation proposed by Anandan, which can describe the difference of geometries directly related to the [math]L^2[/math] space we explore as a Cauchy Schwarz spacetime. My ultimate hope is that it will catch on that the latter gives a natural mechanism for fluctuations in spacetime, as we relate fluctuations to the energy time relationship [math]\Delta E \Delta t[/math]. The commutation relationship known as the spacetime uncertainty is established to satisfy a direct interpretation into the antisymmetric tensor, [math]R_{\mu,\nu} = [\nabla_x, \nabla_0] = \nabla_x \nabla_0 - \nabla_0 \nabla_x \geq \frac{1}{\ell^2}[/math] That is, a space [math]x[/math] and [math]0[/math] (time) notation. I worked out the Christoffel symbols and I calculate in the normal way as two connections: [math][\nabla_i,\nabla_j] = (\partial_i + \Gamma_i)(\partial_j + \Gamma_j) - (\partial_j + \Gamma_j)(\partial_i + \Gamma_i)[/math] [math]= (\partial_i \partial_j + \Gamma_i \partial_j + \partial_i \Gamma_j + \Gamma_i \Gamma_j) - (\partial_j \partial_i + \partial_j \Gamma_i + \Gamma_j \partial_i + \Gamma_j \Gamma_i)[/math] [math]= -[\partial_j, \Gamma_i] + [\partial_i, \Gamma_j] + [\Gamma_i, \Gamma_j][/math] From here, we reinterpreted this in terms of the Cauchy Schwarz inequality to give spacetime an ''instrinsic relationship'' to the uncertainty principle - which may serve as an origin to fluctuations in spacetime - at least this was my motivation - I later discover through more investigation this makes it part of [math]L^2[/math] space and thus, a finite dimensional Hilbert space. The expectation of the uncertainty is the mean deviation of curvature in the system is: [math]\sqrt{|<\nabla_i^2>< \nabla_j^2>|} \geq \frac{1}{2} i(< \psi|\nabla_i\nabla_j|\psi > + <\psi|\nabla_j\nabla_i|\psi>) = \frac{1}{2} <\psi|[\nabla_i,\nabla_j]|\psi> = \frac{1}{2} <\psi | R_{ij}| \psi > [/math] [math] = \frac{1}{2} < \psi |- [\partial_j, \Gamma_i] + [\partial_i, \Gamma_j] + [\Gamma_i, \Gamma_j]| \psi >[/math] I also speculate in terms of the spacetime uncertainty, anticommutation will exist in the Bianchi identities. The Bianchi identity is true up two three Cyclic Christoffel symbols: [math]R_{\sigma \rho [i j]}g^{\sigma \rho} = \partial_i \Gamma_{j} - \partial_j \Gamma_{i} + \Gamma_{i} \Gamma_{j} - \Gamma_{j} \Gamma_{i}[/math] [math]R_{\sigma i[j \rho]}g^{\sigma i} = \partial_j \Gamma_{\rho} - \partial_{\rho} \Gamma_{j} + \Gamma_{j} \Gamma_{\rho} - \Gamma_{\rho} \Gamma_{j}[/math] [math]R_{\sigma j [\rho i]}g^{\sigma j} = \partial_{\rho} \Gamma_{i} - \partial_i \Gamma_{\rho} + \Gamma_{\rho} \Gamma_{i} - \Gamma_{i} \Gamma_{\rho}[/math] You can write these three relationships out in the Bianchi identity, we can write the commutation again, on the indices [math]R_{\sigma \rho[ i j]} + R_{\sigma i [j \rho]} + R_{\sigma j [\rho i]} = 0[/math] Again, the last two indices reveal antisymmetric properties. I worked out a static model for superpositionng will not satisfy the fundamental spacetime relationship! Using J. Anandan's equation which I investigated: [math]E = \frac{k}{G} \Delta \Gamma^2[/math] I noted the equation confused me early on, but it seems it is constructed in the following way [math]<\Delta \Gamma^2> = \sum <\psi| (\Gamma^{\rho}_{ij} - <\psi |\Gamma^{\rho}_{ij}| \psi>)^2|\psi >[/math] I think I realized what was implied by Anandans first equation by noticing his missing constant of proportionality is [math]c^4[/math]. Then an integral of the volume yields the energy [math]E = \frac{c^4}{G} \int \Delta \Gamma^2\ dV[/math] We have argued, that the squared component of the connection can be interpreted in terms of the curvature tensor in Anandan's equation. This is related to the energy of the difference of geometries and that is given now as [math]\Delta E = \frac{c^4}{8 \pi G} \int < \Delta R_{ij}>\ dV =\frac{c^4}{8 \pi G} \int <\psi|(R_{ij} - <\psi |R_{ij}| \psi>)|\psi>\ dV[/math] This is actually related to the difference found in Penrose's model of an induced gravitational collapse in a superpositioned system - albiet, ours is quantum geometry related directly to the Riemann tensor. You may have noticed, the energy equation that describes the difference in superpositioned geometry ~ [math]\Delta E = \frac{c^4}{8 \pi G} \int < \Delta R_{ij}>\ dV =\frac{c^4}{8 \pi G} \int <\psi|(R_{ij} - <\psi |R_{ij}| \psi>)|\psi>\ dV[/math] Shares the difference between two expectation values of the system: [math]\sqrt{|<\nabla_i^2>< \nabla_j^2>|} \geq \frac{1}{2} i(< \psi|\nabla_i\nabla_j|\psi > + <\psi|\nabla_j\nabla_i|\psi>) = \frac{1}{2} <\psi|[\nabla_i,\nabla_j]|\psi> = \frac{1}{2} <\psi | R_{ij}| \psi > [/math] That coefficient of [math]\frac{1}{2}[/math] may indeed attach to that energy, just like a kinetic energy term. So really, when you saw this object: [math]<\psi |R_{ij}| \psi>[/math] as we have shown, we had already calculated this identity very early on in the work. So the energy equation is compatible in a Cauchy-Schwarz interpretation of spacetime. How do you vary the expectation value in the equation? [math]<\Delta E> = \frac{c^4}{8 \pi G} \int <\Delta R_{ij}>\ dV =\frac{c^4}{8 \pi G} \int (<\psi|R_{ij}| - <\psi| R_{ij}| \psi>)|\psi>\ dV[/math] The total variation will split each two terms, [math]<\psi|R_{ij}| - <\psi| R_{ij}| \psi>)|\psi>[/math] into [math]<\delta_{a} R_{ij}> = <\psi| R_{ij}| \delta_{a}\psi> + <\delta_{a} \psi |R_{ij}|\psi>[/math] [math]<\delta_{b} R_{ij}> = <\psi| R_{ij}| \delta_{b}\psi> + <\delta_{b} \psi |R_{ij}|\psi>[/math] where the subscript of [math]\delta_{ab}[/math] denotes a ''two particle system.'' So it will become a four-component equation with variations in each term of the wave function. In the main work, we also discussed shortly, my model being related to Penrose's model for the collapse of gravity in a superpositioned state. Penrose has suggested a graviational self energy related to a collapse time model [math]T \approx \frac{\hbar}{E}[/math] And in the Penrose model, the energy is given as [math]E = \frac{1}{4 \pi G} \int (\nabla \phi' - \nabla \phi)d^3x[/math] We can derive a more general case that can be used to measure the density variations of spacetime. Deriving the gravitational binding between any coherent gravitational superpositioning state can be given the following way: The gravitational field inside a radius [math]r = r(0)[/math] is given as [math]\frac{dM}{dR} = 4 \pi \rho R^2[/math] and the total mass is [math]M_{total} = \int 4 \pi\rho R^2 dR[/math] and so can be understood in terms of energy (where [math]g_{tt}[/math] is the time-time component of the metric), [math]\mathbf{M} = 4 \pi \int \frac{\rho R^2}{g_{tt}} dR = 4 \pi \int \frac{ \rho R^2}{(1 - \frac{R}{r})} dR[/math] The difference of those two mass formula is known as the gravitational binding energy: [math]\Delta M = 4 \pi \int \rho R^2(1 - \frac{1}{(1 - \frac{R}{r})}) dR[/math] Distribute c^2 and divide off the volume we get: [math]\bar{\rho} = \rho c^2 - \frac{ \rho c^2}{(1 - \frac{R}{r})}[/math] Were we have used a notation [math]\bar{\rho}[/math] for the energy density. Fundamentally, the equations are the same, just written differently. Notice that [math]\nabla^2 \phi = 4 \pi G \rho[/math] from Poisson's formula, in which we notice the same terms entering [math]\Delta M = 4 \pi \int \rho R^2(1 - \frac{1}{(1 - \frac{R}{r})}) dR[/math] [math]E = \frac{1}{4 \pi G} \int (\nabla \phi' - \nabla \phi)d^3x[/math] So while Penrose suggests calculating the binding energy directly from the gravitational potential [math]\phi[/math] there are ways as shown here, to think about it in terms of the gravitational energy density and the gravitational binding between the two. http://sci-hub.bz/10.1007/BF02105068 Note* It is also possible to write a version of Anandan's equation like the following [math]E = \frac{c^4}{G} \int (\nabla \Gamma)^2\ dV = \frac{c^4}{G} \int \frac{1}{R^2} \frac{d\phi}{dR} (R^2 \frac{d\phi}{dR})\ dV[/math] This part [math]\frac{1}{R^2} \frac{d\phi}{dR} (R^2 \frac{d\phi}{dR})[/math] Is just another way to write a squared product [math]\frac{d\phi}{dR} \cdot \frac{d\phi}{dR}[/math]. And of course, this is just [math]\nabla^2 \phi^2[/math]. We've stated this identity before in an equation - note also, [math]\phi[/math] is dimensionless.
  14. Taxation

    You are right and I was wrong thanks for clearing up my misconception. There is a long running debate that capital gains tax does or does not stimulate investment but if it works at all it dosent work in the manner I described.
  15. Is the Universe infinite?

    There seems to be confusion between the 'observable universe' and 'universal domains'. A domain is a volume of the universe, originally in causal contact, for which quantum fluctuations of the vacuum energy triggered inflation, and subsequent symmetry breaks, at different 'times' and in different ways. These domains would be separate from each other and may have different physical laws. IIRC they would be characterized by magnetic monopole production at the domain boundaries . And they are purely speculative as they would lie outside our observable universe. The observable universe, as Mordred has pointed out, is a causality sphere, and is different for each observer. It is a mathematical construct, defined by the distance light/information could have travelled to reach the observer since the Big Bang. In effect, the person standing a meter to your left, has a different observable universe than you; His extends a meter farther to the left, and is a meter shorter to the right. So when Strange says there could be an infinite number of observable universes in a finite universe, if space isn't quantized, that means the universe can be infinitely subdivided into different observable portions, as each will always be different.
  16. Pet Stories

    My cat never kills anything it brings in the house. It just brings them in for playmates. I've found lizards, mice and chipmunks running around inside the house. If she brings in a snake I'm getting rid of her.
  17. OT from how to turn a believer

    and we know there are perfectly logical explanations for the things that people claim are proof of god. that doesnt stop people ignoring those and still choosing the god. just like i can ignore that the most likely explanation for getting easter eggs was my parents when i wasnt looking, and choose to believe that it was a mythical easter bunny. cause that makes me feel good. as drp just said. a warm fuzzy feeling in your heart doesnt constitute proof that what you believe happened, actually did happen. and you are lying to yourself if you try to make it so.
  18. Consciousness and Evolution

    This is incredibly simple! We just can't see it because we don't think "right" because we use symbolic language. Things want to live and consciousness is the means to do it. Evolution is simple as well but plays out in a very complex world that is always changing and eradicating "wrong" behavior".
  19. Pet Stories

    My lamb (Bob), escaped his cage once and wondered into my patio area, where he found a mop leaning up, and proceeded to have an intimate experience with the mop. It was damn cheeky of him, I think I still have a video of that. RIP Bob 2016-2016, you sure did taste good.
  20. Is the Universe infinite?

    Maybe you should read the article: "And what they teach us is that not only is the Universe consistent with being flat, it’s really, really, REALLY flat! If the Universe does curve back and close on itself, its radius of curvature is at least 150 times as large as the part that’s observable to us! Meaning that — even without speculative physics like cosmic inflation — we know that the entire Universe extends for at least 14 trillion light years in diameter, including the part that’s unobservable to us today."
  21. Smuggling Nuclear Weapons

    Good point. If a nuclear weapon is caught being smuggled into a country, is there a way to determine where it originated? Is there a way to build one so that it's origin is not determinable?
  22. The Official JOKES SECTION :)

    Q: Do you think the noise of playing children is nuisance? A: No, I sound proved my basement pretty well.
  23. Pet Stories

    I'm glad to hear about the happy ending.
  24. Is the Universe infinite?

    Thanks So, as the Observable Universe is about 100 BLY then the minimal estimated size of our Universe is: 15 trillion Light year. Is it correct? Sure. However, can you please elaborate if the speed of light has any affect on the WMAP data as stated:
  25. How Long Earth Can Stand The Pollution?

    The challenge with your question is we must make certain assumptions about the global political response. Before we can model the possible future, we must start by making decisions about humans will change their behaviors (and predictions are hard, especially about the future!). The answer will be extremely different if we stop polluting 100% immediately than it will be if we gradually stop polluting over the next 100 or 1,000 years or if we don't change at all. Note that I include CO2 in my use of the word "pollution," but intend to refer to more than just that. Earth has survived massive comet impacts, extreme volcanic and seismic activity, has gone through ice ages and solar storms and hosted vast epochs of life and change and much more. The earth will be fine. It's us and the other life on it that could be in trouble. Some useful information and helpful links available for you to explore here: https://www.skepticalscience.com/co2-pollutant-advanced.htm
  26. Is the Hubble Shift a relativistic illusion?

    That is a primary problem. "Intuitive" does not work. "Intuitive" based on GR gives us Dark Matter and Dark Energy and an illogical Big Bang accelerating expansion of the cosmos. We see ourselves moving "through" space instead of as being within an evolving quantum continuum with no actual depth. We perceive a constant speed of light, but adjust the length of a meter and the duration of a second to keep it constant. Einstein showed us that it is not intuitive, but simply relativistic. If you post again it will take me some time to reply as I am off to work after being gone for a week and have much to catch up on.
  27. Is the Hubble Shift a relativistic illusion?

    On a more constructive note, it sounds like you are swapping expanding space for a changing "rate of time". My (limited) understanding is that this is a well known coordinate transformation but it is not often used because (for most people) it is a less intuitive model and it can make things more complex (e.g. the speed of light is not constant).
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