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Everything posted by Mordred
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I need help with Doppler's effect understanding
Mordred replied to frostysh's topic in Classical Physics
No the laws of physics are the same however you still measure different wavelengths between observers That is NOT an invariant quantity. If all observers measured the same quantity you would never have redshift to begin with... -
I need help with Doppler's effect understanding
Mordred replied to frostysh's topic in Classical Physics
Also don't confuse Galilean invariance with invariant quantity. Galilean invariance states the laws of physics are the same in all inertial frames. Though Newton believed in an absolute frame. This does not mean measured quantities are also invariant. Forgot to add that above Now let's apply that. Take two observers one observer is moving. One is not. Remove all other references except the wavelength itself. Neither observer will be able to tell who is moving or who is not. They will only be able to tell they are moving towards or away from each other. (Assume they are transmitting the same signal ) after all you must know the original frequency/wavelength to know if there is a redshift. So mathematically [latex] ( x=\acute {x}-vt)=(\acute {x}=x-vt) [/latex] either x or primed x can be the moving observer. There is no distinction or change that makes one frame more priveliged than the other as the relations are symmetric. -
I need help with Doppler's effect understanding
Mordred replied to frostysh's topic in Classical Physics
You have a different meaning to invariant quantities then to standard definition. An invariant quantity means all observers agree on the value. The constant c is one example under relativity. All observers in every reference frame will measure the same value. This isn't the case with wavelength different observers will measure different wavelength values hence the terms redshift and blueshift. So how can you claim wavelength is invariant under that definition ? Take the following relations [latex]\frac{\Delta_f}{f} = \frac{\lambda}{\lambda_o} = \frac{v}{c}=\frac{E_o}{E}=\frac{hc}{\lambda_o} \frac{\lambda}{hc}[/latex] [latex]f=\frac{c+v_r}{c+v_s}f_o[/latex] This is the Doppler shift formula c=velocity of waves in a medium Vr is the velocity measured by the source using the source’s own proper-time clock(positive if moving toward the source vs is the velocity measured by the receiver using the source’s own proper-time clock(positive if moving away from the receiver) The above are for velocities where the source is directly away or towards the observer and for low velocities less than relativistic velocities. A relativistic Doppler formula is required when velocity is comparable to the speed of light. The relativistic Doppler is given by [latex]v_{observed }=v_{source}\sqrt{\frac{1+\frac {v}{c}}{1-\frac{v}{c}}}[/latex] This describes a variant wavelength and hence a variant frequency which also means the corresponding energy is also variant between different observers. In the last case c is the constant c By the way the definition of invariant and variant quantities do not change between relativity or Galilean transformations. It is the same definition Start with the Galilean transformations [latex]x=\acute {x}-vt [/latex] [latex]y=\acute {y}[/latex] [latex]z=\acute {z}[/latex] [latex]t=\acute {t}[/latex] Then apply the equations on the following https://www.google.com/url?sa=t&source=web&rct=j&url=http://users.physics.harvard.edu/~schwartz/15cFiles/Lecture21-Doppler.pdf&ved=2ahUKEwjG8NSM--DjAhURsp4KHbGmCtkQFjAQegQICBAB&usg=AOvVaw2-wPdgX3Qsq1K7kWG6zuG0 This applies [latex]c_s [/latex] for the speed of sound. (Non relativistic Doppler it describes how wavelength varies (variant) between observers -
Let's clarify a bit on the reference to graphs and subgraphs in that quoted section. As noted this article loses a lot on technicalities. That section is referring the graphs in reference to the Feynman path integrals the internal lines being the propogators Ie virtual particles but in QFT it's simply field influence QFT treats all particles as field excitation. Real particles are observable Ie a quanta of action minimal. The propogators propogators the operators and the Observable operators operate on the propogators. (Much like space tells matter how to move matter tells space how to curve lol) Anyways this is an example. The internal wavy line is the propogators while the external lines the Operators. [math]\array{e^+ \searrow &&\nearrow P^-\\&\leadsto &\\ e^-\nearrow &&\searrow P^+}[/math] Gauge bosons are offshell they are part of the virtual particle family hence in the propogator integrals. The operators Ie real particles (more accurately observable particles ) are the external line path integrals.
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Here is a paper discussing the issue with a proposed methodology. It is simply one example of a plethora of proposed methods. Now onto the comment made by Uncool.. This above process involves the running of the coupling constants in terms of symmetry breaking.. as you can see gravity becomes emergent after the breaking. Another way this can be described is gravity drops out of thermal equilibrium. Here is the article keep in mind it is but one example. PS on phone it is an arxiv article... https://www.google.com/url?sa=t&source=web&rct=j&url=https://arxiv.org/pdf/1112.5104&ved=2ahUKEwjXnNqhz-DjAhVlHzQIHfzuAjgQFjABegQIBhAB&usg=AOvVaw2Q8l6DtEpIv_3n6OaoqHUh Here is another relevant section with regards to action being involved it's an essential ingredient to QFT. Hope that helps
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Ok don't treat spacetime as some materialistic fabric for starters. Those descriptives you read about are misleading analogies. The problem with gravity on microscopic scales is that the effect of two individual particles would have on each other due to their mass terms are so insignificant we will likely never be able to measure any influence. There wouldn't be enough to cause an "action" of displacement. Action is equivalent to a quanta in units. Hence the expression a quanta of action. Anything below this scale can never be measured even with a hypothetical perfect detector. Yes significant mass however does affect individual particles, muon decay is one example. Now even if we were to discover the graviton, this may or may not solve the divergence problem with renormalization of the Poincare group. This is one of the primary reasons we have not been able to unify gravity. The other being able to determine if gravity will unify by running of the coupling constants with regards to symmetry breaking. To explain this fully would require you to have a very strong understanding of gauge group theory in regards to particle physics. Ie the Standard model of physics had eighteen primary parameters. However MSSM had 110.
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Physics conjecture - Split from Spacetime is doomed.
Mordred replied to clive slocombe's topic in Speculations
Well as I cannot see any of the details I cannot comment lol. At OP your going to have to post your long spiel here. Anyways time dilation goes along with length contraction. Both are required to keep c invariant. You cannot keep c invariant with time dilation only. Length contraction and time dilation are simultaneous. This is one of main reasons why spacetime is not seperatable -
I need help with Doppler's effect understanding
Mordred replied to frostysh's topic in Classical Physics
Well in one of the posts above it was mentioned that wavelength was invarient. It isn't how one measures wavelength is observer dependent and will vary between observers. Normal everyday Doppler that doesn't include time dilation effects will follow the Galilean transformation rules, however once relativity effects become significant then one must use the relativistic Doppler formulas to account for this. The transformation rules for the latter case being the Lorentz transformations of SR. https://en.m.wikipedia.org/wiki/Relativistic_Doppler_effect For example the speed of sound is non relativistic in Earth's atmosphere so the normal Doppler works fine. -
WHY electrons move in orbitals around nuclei
Mordred replied to Oldand Dilis's topic in Speculations
The simple truth can often hurt, that doesn't change the truth. Math is fundamentally vital in physics. You must be able to quantify interactions such as orbitals. We have been pointing this out for good reasons. Without the proper details such as the required math your theories will be wasted. Calling us snobs for pointing out thus truism will not change this. My very first day of physics and pretty much everyday after that involved learning math graphs etc. -
WHY electrons move in orbitals around nuclei
Mordred replied to Oldand Dilis's topic in Speculations
To make testable predictions language is next to useless. A testable prediction is only viable through the mathematics. For example Newton's law predicts f=ma. This formula has withstood the tests of time for centuries until one had to consider relativistic effects. It's still incredibly robust in everyday applications. Though one can express that formula using language you are simply replacing the formula with a direct translation not an interpretation. It is the mathematics that is vital. Words simply assist to understand and interpret the relations shown under math. As someone who has studied different physics theories for over three decades unless an article contains roughly 50 to 75 % math I tend to ignore that paper. -
WHY electrons move in orbitals around nuclei
Mordred replied to Oldand Dilis's topic in Speculations
Lol it would take far too long to post particle decay via QFT "S " matrix treatments. I would need to write a textbook -
WHY electrons move in orbitals around nuclei
Mordred replied to Oldand Dilis's topic in Speculations
Funny I thought this thread was about orbitals... Computer modelling without math yeah right sure ya did. What did you use paint ? Surely you had to use math to generate a working computer model. So post the math. So which is it ? If you claim to solved it using primary school math at least post that. However in the same sentence you state without math... Funny how those two statements don't match... -
WHY electrons move in orbitals around nuclei
Mordred replied to Oldand Dilis's topic in Speculations
Oh sure then let's see you mathematically describe frequency with your 7 dimensions. You have yet to post any formulas in this thread. Yet claim you have three time dimensions and three spatial dimensions with one in a field. Do you even know what a dimension or field means ? As what you stated makes literally no sense whatsoever by any accepted definition. -
Well it still requires improvement. You have based a lot on this Einstein fundamental metric however your not following any of the rules for his tensors. I noticed you also avoided my strongest argument of expansion evidence which follows thermodynamic relations and evidence that does not involve redshift. Anyways regardless of being published on that site, that doesn't mean it's necessarily correct. Surprising enough that isn't the purpose of a peer review. Not even on sites such as arxiv. You can read their peer review disclosure to understand what I mean by that. Needless to say there isn't sufficient work nor evidence within the paper to sway mainstream views on dark matter or resessive velocities in excess of c. It is well established that this is an apparent velocity not a true velocity. One other side note different H values alter the age of the universe estimates. Did you calculate the age for 70 Km/s/Mpc or did you simply look up the age value because I don't believe 70 gives the age in your document.
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Time to experience without limit. If your bored find something new to experience. Every moment is what you make of it. It would take an eternity to experience and learn everything...
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Reducing the nuclear threat by reducing the tactical answer time
Mordred replied to MaximT's topic in Engineering
Military subs already have those https://en.m.wikipedia.org/wiki/Submarine_communications_cable They also approved use of modems via STANAG in 2017 for underwater modems -
Sort of like getting a tattoo once you get your first one tends to want more and more
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True enough, I for one have no issue with genetic cures for illness or ailments however I wouldn't invest in modification simply to make my children superior. We all have boundaries we won't cross.
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As a parent and grandfather I can attest that one will go through any possible measure to ensure your children and grandchildren have the best you can provide in terms of their health and wellness. Quite frankly it is hard to find fault in that feeling as it is natural even among animals. It is a natural response to always want the best for your children. Would you deny a child of yours treatment simply due to being genetic involved ?
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In this case start with a large body survey questions. Design the question are with neurological processes in mind. Ie tingling sensations is a sign of oxygen deprivation, look into other side effects that can be induced due to reduced oxygen levels to vital organs such as the brain. Figure out which feelings can be eliminated due to oxygen deprivation. How is that for a start? Instead of immediately jumping into supernatural phenomena look into side effects such as the one mentioned above. (For the record I have practiced meditation for several decades. I can induce a wide range of feelings throughout my body. At one time I could slow my heart beat to 10 per minute) Not once did I attribute any feelings to a supernatural reason. Meditation has stress management health benefits. However one should never confuse self induced feelings with supernatural causes. The mind is cabaple of many different interpretations of signal responses from neurons. Lol side note it drives my wife crazy that no matter how many mosquitos bite me I don't itch. (I taught myself to ignore that sensation)
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They can more readily follow conjecture and verbal word play than mathematics or proper scientific analysis. Over 3 decades experience to see that habit lmao
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A scientific fact without reliable scientific data good luck. Much of what is described depends on the individual feelings. The descriptive are primarily interpretations so too are the descriptive.
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No, a shrink ray is science fiction. Chemical bonds within atoms depend on energy levels. So too does bonds of multi atom configurations. The spacing of protons, neutrons and electrons have a reason in nature. The details of such would be a lengthy thread just on one example. However they are fundamental properties within our universe. Same goes for how dense certain materials can get before other factors come into play. Google neutron stars for one example. You increase density you change the temperature which changes stability between bonds
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Orthogonal refers to when two vectors are 90 degree perpendicular to one another. Coordinates can be regarded as vectors so the x axis is orthogonal to the y axis. In Cartesian coordinates with no time dilation the ct,x,y,z axis are orthogonal. A little math trick anytime you see a tensor with only the diagonal components non zero the tensor is orthogonal Here is the Minkowskii tensor as an example [latex]\eta_{\mu\nu}=\begin{pmatrix}-c^2&0&0&0\\0&1&0&0\\0&0&1&0\\0&0&0&1\end{pmatrix}[/latex]
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Let's add some greater detail. The purpose of the metric tensor is to define a coordinate basis. For example Flat space [latex]\mathbb{R}^4 [/latex] with Coordinates (t,x,y,z) or alternatively (ct,x,y,z) flat space is done in Cartesian coordinates. [latex] ds^2=-c^2dt^2+dx^2+dy^2+dz^2=\eta_{\mu\nu}dx^{\mu}dx^{\nu}[/latex] In this case [latex] g_{\mu\nu}=\eta_{\mu\nu}[/latex] [latex]\eta_{\mu\nu}=\begin{pmatrix}-c^2&0&0&0\\0&1&0&0\\0&0&1&0\\0&0&0&1\end{pmatrix}[/latex] spherical polar coordinates [latex](x^0,x^1,x^2,x^3)=(\tau,r,\theta,\phi)[/latex] [latex] g_{\mu,\nu} =\begin{pmatrix}-1+\frac{2M}{r}& 0 & 0& 0 \\ 0 &1+\frac{2M}{r}^{-1}& 0 & 0 \\0 & 0& r^2 & 0 \\0 & 0 &0& r^2sin^2\theta\end{pmatrix}[/latex] line element [latex]ds^2=-(1-\frac{2M}{r}dt)^2+(1-\frac{2M}{r})^{-1}+dr^2+r^2(d \phi^2 sin^2\phi d\theta^2)[/latex] Where as in Minkowskii space in rotating space about the z axis. (Sagnac effect) [latex] g_{\mu,\nu} =\begin{pmatrix}-(1-\frac{\omega^2r^2}{c^2})& 0 & \frac{\omega r^2}{c}& 0 \\ 0 &1& 0 & 0 \\\frac{\omega r^2}{c}& 0& r^2 & 0 \\0 & 0 &0&1\end{pmatrix}[/latex] As you can see entries depend upon coordinate basis which is the purpose of the metric tensor. The determinant will vary depending on metric changes.