Everything posted by swansont
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Light absorption and linewidth (split from A rational explanation for the dual slit experiment)
Since the particles need not be entangled for an excitation, I concur that this is indeed a fairy tale.
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Oumuamua - mathematical question
You can look at the Hohmann transfer equations https://en.wikipedia.org/wiki/Hohmann_transfer_orbit and see that they only depend on the mass of the planetary body, as long as the mass of the craft is small in comparison. One reason you might need to know the mass of a craft is if it is going to be providing thrust, but as long as the motion is passive, the mass drops out of the equations.
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Hi, I have a dimensional problem
The cosmological constant energy density "units" are for when you set G = c = 1, so you can't really distinguish between the two uses of the cosmological constant (and is the answer to why it doesn't have units of energy) Is that also happening for your other equation? i.e. was it from an equation with normal units, or one where they were ignored? Since you're asking this without providing context, it's very difficult to see if this is the problem https://en.wikipedia.org/wiki/Cosmological_constant The cosmological constant has the same effect as an intrinsic energy density of the vacuum, ρvac (and an associated pressure). In this context, it is commonly moved onto the right-hand side of the equation, and defined with a proportionality factor of 8π: Λ = 8 π ρvac , where unit conventions of general relativity are used (otherwise factors of G and c would also appear, i.e., Λ = 8 π ρvac G / c4 = κ ρvac , where κ is Einstein's rescaled version of the gravitational constant G). It is common to quote values of energy density directly, though still using the name "cosmological constant", using Planck units so that 8πG = 1. The true dimension of Λ is length−2. IOW, Λ = κ ρvac and you call it an energy density by assuming κ is 1. But it's not actually 1 I meant "where in standard physics literature did this equation come from" You need to have started with mainstream physics at some point.
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Hi, I have a dimensional problem
Why doesn't it have units of energy? Can you show where you got this equation?
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US trend toward authoritarianism? (split from Comparing Corona Virus Success Stories with Abysmal Failures)
And what if you don't share in the ideology? Hence the very strong push to make sure that opponents have difficulty voting, and that a majority representation can be elected with a minority of votes.
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Oumuamua - mathematical question
No. Momentum is mass*velocity They accelerate at the same rate, so they gain velocity at the same rate. The one with more mass will have more momentum The one with greater mass has more momentum, yes, but it loses more momentum
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8061 and its root from 4d to 3d from .1
! Moderator Note You were told to stop
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Quantum Theorists: Amateur Projects
! Moderator Note As the requested summary/abstract has not been posted, this is closed. Do not post anything similar. (I'd say don't post on this topic, but it's not clear what this topic is)
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Oumuamua - mathematical question
They have momentum, individually. The system does not, because the earth moves imperceptibly toward the dropped mass, with the imparted velocity being inversely proportional to the mass. IOW, the dropped object of mass m acquires a speed v, so it has a momentum mv (downward). The earth has this same momentum upward, which is also MV (M being the mass of the earth and V being its velocity) mv = MV so the earth would have a velocity of V = mv/M in the upward direction But the object's mass, be it 1 kg or 100 kg or 1000 kg, is so small compared to the earths mass of about 6 x 10^24 kg that there is no way to measure V. For all practical considerations, the earth remains at rest. (a similar argument applies to the sun, whose mass is about 2 x 10^30 kg, and any small object interacting with it) When you move out of a gravity well you would slow down, because of gravity, absent any independent propulsion. For an individual object, momentum is conserved when there is no net force acting on it, so it would not apply to such an object subject to gravity.
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Cancel Culture-Split from: Jordan Peterson's ideas on politis
So, not "cancel culture" but another example of political buzzword-pimping (from https://www.washingtonpost.com/politics/2021/11/15/most-republicans-oppose-teaching-kids-about-lingering-effects-racism/ ) Things like this, or migrant caravans, or whatever the manufactured outrage du jour is, gets played up in the media - especially right-wing media - whenever the base needs to be riled up So hey, if you are getting backlash from something you said or did? Blame cancel culture to deflect the controversy away from yourself. Attack anyone trying to hold you accountable for your actions or words.
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Oumuamua - mathematical question
Mass typically drops out of these calculations, at least when you analyze the simplest systems. It will come into play because you can't treat it as a point object, but that might or might not be a large factor. As I recall, the object had rotational motion, and if that changed, you'd need to account for the energy and momentum. But as far these factors can be ignored, the mass won't matter. A baseball or an asteroid would have the same motion. If the sun were accelerating in some strange way we'd be accelerating along with it. Our motion about the sun and around our axis is analyzed with significant scrutiny. Such an acceleration would be noticed if it were large enough to matter.
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Oumuamua - mathematical question
You assume the sun it at rest and find the motion relative to the sun. They are in different frames, because there is relative motion. But if the motion is inertial, you can treat either as if it were at rest, and all of the physics will be the same. If one is accelerating, you'll see evidence of non-inertial motion (which we already have; Oumuamua felt an acceleration from the sun, regardless of any self-propulsion) The sun, being much more massive, would only have a tiny acceleration, which can safely be ignored, since we won't have the precision in the data to discern it. If you do the analysis in the sun's frame of reference, it simplifies everything.
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Light as a wave or particle (split from A rational explanation for the dual slit experiment)
I say it does (and this is what physics tells us), since you have a wave that has a characteristic size of its wavelength, and you apparently have no explanation or example of a localized wave to offer. Is that supposed to be an answer? If the light passes through a vapor cell it has not interacted. It has nothing to do with its destination. No link to the article, or a citation; the paper is also on ArXiv. https://arxiv.org/pdf/1007.0104.pdf And if you read further, you find that they didn't expect to find any evidence. Sometimes you do experiments where the expected result is small, on the off chance that you find something, showing the model to be wrong, and discovering new physics (I have been involved in such experiments, No, we didn't find any new physics.) "This cross section is extremely small in the optical domain where high brightness sources exist" Their results placed an upper limit of the cross-section, but that was still ~18 orders of magnitude larger than the QED prediction. So this is NOT an example of "Many have claimed that photon particles should collide and scatter when laser beams cross" since they acknowledge the cross section is very small. That's a dodge. "Anyone" didn't make the claim, you did. But of course you are. Even if one subscribes to "it's a wave and only a wave" light has energy, light exists, and light is not matter. Unless you want to construct a whole bunch of new physics, which you haven't done, this doesn't wash.
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Oumuamua - mathematical question
You can get a pretty good solution with just Newton's laws of motion and Newtonian gravity, as long as there were just the two bodies. Which is a reasonable approximation absent any close fly-by of a substantial body. The sun can be treated as if it were at rest; any deviation from an inertial frame can be ignored. People can predict comets pretty well
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US trend toward authoritarianism? (split from Comparing Corona Virus Success Stories with Abysmal Failures)
The trend toward authoritarianism predates any current economic stress and the pandemic, though. Parts were in place even before TFG ran for office. Politicizing masks and vaccines, and other pandemic-related issues are only a part of the overall picture, and just a convenient tool being used as leverage.
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NASA discovery proves Dark Matter doesnt exist and disproves standard model of cosmology [FALSE!]
In a sense that's what's happening, owing to the expansion - it becomes redder, meaning it has less energy. But if you mean can it lose energy via some interaction with matter, that's scattering, which tends to change the direction of the light. By virtue of the light getting to us, without being smeared out, we know it hasn't done that. Specific refutations would require the models to be presented, so one could compare predictions with data. A detailed model would be able to predict how the redshift would occur and quantify the effects. People have proposed tired light models, and they don't fit with the evidence http://www.astro.ucla.edu/~wright/tiredlit.htm
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Banned/Suspended Users
ravell has been banned as a sockpuppet of Bart and bart2
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Did the American education system did such a poor job at promoting STEM that "Millennials" were less interested in becoming astronauts?
US television saw > 500 new shows + miniseries in 2020 (and 2019, so it's apparently not an anomaly) Just over 1% is hardly an explosion. It would be strange of that genre wasn't explored to this minimal extent, with all the shows being made.
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Oumuamua - mathematical question
This is an accelerometer using a proof mass. I’m familiar more with attempts using atoms as a proof mass, http://ridl.cfd.rit.edu/products/pfq2 speaker videos/slides/PfQ2 July 2020 Choy.pdf Start with slide 6
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Oumuamua - mathematical question
But you can do a measurement to see if you’re the one accelerating. If I toss a ball to you and we’re on a platform with perpendicular acceleration, the ball will deflect in the opposite direction. (This principle is used in some inertial sensor designs.)
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Oumuamua - mathematical question
While velocity is relative, acceleration is not. You can tell if you are accelerating.
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Banned/Suspended Users
tar has been suspended for repeatedly bringing up a pet theory (from a locked thread, no less) in mainstream discussion, and failing to post in good faith (opening up a mainstream thread to bring up the pet theory)
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Size of an event in Spacetime
! Moderator Note If you are able to explain the idea, you should have done so when you had the chance. But you did not, and continuing to raise this issue is against the rules. You can insist that you understand relativity, but the evidence is that you do not.
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Light absorption and linewidth (split from A rational explanation for the dual slit experiment)
Not periodic motion, as such, since motion is not directly implied. (it’s inferred by imposing classical notions on QM, and that usually ends up causing problems) QM avoids saying anything about trajectories in situations like the particle in a box. It’s one of the things that distinguishes it from classical, and also why free body diagrams are not part of QM.
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What is Justice?
Didn’t say it was. But generally a society converges on a set of laws. And is it the same as dogs? And for the same reasons? This wasn’t the issue. Also not the issue.