PeroK's latest activity
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PeroK reacted to Filip Larsen's post in the thread Undergrad Practical cosmic speed limit for macroscopic objects? with
Informative.
Indeed. Breakthrough Starshot comes to mind. -
PeroK replied to the thread High School Does acceleration affect impact energy vs constant velocity?.Your understanding is not correct. -
PeroK replied to the thread Announcement PF Member Awards 2025 Coming Soon!.An award for crackpot of the year would be fiercely contested. -
PeroK reacted to JimWhoKnew's post in the thread Undergrad The imaginary part of the wave function with
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Introductory textbooks usually deal a lot with time-independent Hamiltonians of the form$$H=\frac{\mathbf{P}^2}{2 m}+V(\mathbf{x})\quad... -
PeroK reacted to renormalize's post in the thread Undergrad The imaginary part of the wave function with
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I don't see that at all. Consider, e.g., Griffiths & Schroeter, Introduction to Quantum Mechanics (3rd ed.) in which the authors solve... -
PeroK reacted to JimWhoKnew's post in the thread Undergrad Klein-Gordon equation in the nonrelativistic limit with
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From relativity, having the rest mass as the limit of the energy when the kinetic contribution goes to zero, is a welcome feature... -
PeroK reacted to JimWhoKnew's post in the thread Undergrad Klein-Gordon equation in the nonrelativistic limit with
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Try to back-substitute$$\phi=\psi\exp{\left[\frac{i}{\hbar}m_0c^2t\right]}$$in equation 1.32 . What equation does ##\psi## obey in this... -
PeroK reacted to Ibix's post in the thread High School Estimates — True Size of the Universe? with
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The problem with this one is the finite size. People conflate the increase in volume of the finite lump of dough with the expansion... -
PeroK reacted to robphy's post in the thread Undergrad Derive the Lorentz transformation in Minkowski four-dimensional spacetime spacetime with
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First, I acknowledge what you say about spacetime diagrams being confusing. So, some of my efforts have tried to develop additional... -
PeroK replied to the thread High School Estimates — True Size of the Universe?.This is a property of an infinite space. And infinite sets in general. For example, in one sense there are twice as many whole numbers... -
PeroK replied to the thread Student of Astronomy and planetary science.If you look for the top 10 cosmology forums, then the first three will be in that list. -
PeroK reacted to A.T.'s post in the thread Undergrad Why if net force=zero, moment at any point is same? with
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If ##\vec{F_{net}}## is the net force, and ##\vec{M_{net,a}}## is the net moment around the point ##\vec{a}##, then the net moment...