Observed Definition and 190 Threads

I don’t like CI. But I was always thinking that CI is an idealistic interpretation, based on the consciousness and the existence of intelligent observers. In Bohr’s time it was simple. He believed in a sharp line between quantum world and macroscopic world. Quantum event Q was registered by...

Homework Statement The muon is an unstable particle that spontaneously decays into an electron and two neutrinos. If the number of muons at t = 0 is N_{o}, the number at time t is given by N = N_{0}e^{-t/\tau}, where \tau is the mean lifetime, equal to 2.2 \mu s. Suppose the muons move at a...

In Wheeler and Taylor's 'Exploring Black Holes', on pages 3-12 and 3-13, the bookkeeper measure of radial velocity (i.e. radial velocity as measured from infinity) is derived. Basically the equation for 'Energy in Schwarzschild geometry' is established-...

Relativity and observed length of a moving object! Homework Statement A box is cubical with sides of proper lengths L1 = L2 = L3 = 2.3 m, as shown in the figure below, when viewed in its own rest frame. This block moves parallel to one of its edges with a speed of 0.89c past an observer...

What has been the longest photon wavelength actually observed?

1) In a lottery there are 10 tickets numbered 1,2,3,...,10. Two nubmers are drawn for prizes. You hold tickets 1 and 2. What is the probability that you win at least one prize? Method 1: assume order matters (different order=>different outcome) P(win at least one prize) = P(win exactly one...

I'm going to state that two inertial bodies that close distance on each other will (becouse of loss of simultaneity)observe time dilation. Also i will state that when one body accelerates it will actually time dilate from its frame of origin. So with this stated, if a rocket traveling under...

"...the observed masses of the particles.." R. Feynman Feynman wrote: "Throughout this entire story there remains one especially unsatisfactory features: the observed masses of the particles, m. There is no theory that adequately explains these numbers. We use these numbers in all our...

Why is it that if an orbiting space station is observed to remain always vertically above the same point on Earth then the observer must be on the equator of Earth?

I am struggling with an Atoms and Nuclei past paper question, if someone can help please. In a Stern Gerlach experiment, how many traces on the plate would be observed if instead of hydrogen a)helium b)boron (atomic number 5), are used? [Hint: Boron will exist in 2L-S coupled states] I...

Could it be that an observed object moving back in time is indistinguishable from an object moving forward in time? To measure the signed rate of time flow we could use a light clock with 3 mirrors (A, B, C) reflecting the light beam in a triangle, in clockwise direction (A -> B -> C …). If...

Can somebody please help me with this question? Obviously when we observe an event it has not occurred at the time that we observed it occurring as light travel time must be taken into account. However within our frame is the observed duration of an event (ie a star exploding) considered...

Homework Statement Consider a double-star system with two stars, A and B, in circular orbits of the same period T about their center of mass. The Earth is in the plane defined by these orbits at a distance R of many light-years. Let the speed of A in its orbit be u; then at any instant it has...

To jump from a single celled organism to a multicellular one, we need beneficial addition mutations in DNA sequences. My question is this: has this phenomena ever been observed? By beneficial I mean a mutation in the genotype that serves to cause some phenotype that can be used by an organism...

Neutron Stars (black hole?) picture. maybe this not news. Published in something like "physics review of celestial body". I attached a pic, but it does not manage to show.

http://science.nasa.gov/headlines/y2007/07may_bigsupernova.htm?list45222 "Of all exploding stars ever observed, this was the king", said Alex Filippenko, who leads two of the observation teams involved in the discovery. The star that exploded was 150 times as massive as the sun. The explosion...

Hello, Could you please tell me roughly, how many galaxies have been observed? Thank you, Glynis

Hi :) What is the maximum observed acceleration a body (a matter) can have? I suppose it may be the acceleration of matter of supernova explosion, how much is its value? (I thought also acceleration of particles in particle colliders is big, but it seems there is no sense to ask about...

http://www.physorg.com/news78650511.html One millimeter oil droplets interfering with themselves... cool. :biggrin: It looks like there doesn't seem to be an upper boundary size for quantum mechanical phenomenom.

Hubble has observed a Uranian satellite shadow tranist for the very first time. More info and hi-res pictures available here: http://hubblesite.org/newscenter/newsdesk/archive/releases/2006/42/image/a

it is observed that Mars is somewhat brighter when in opposition (ie. sun- Earth - Mars in that order) that at other times. How can this be explained using a) The Ptolemaic model and b) The Copernican model of the solar system. (Assume that Ptolomy's construction describes the actual motion...

Local coordinate system in GR observed. If one considers coordinate systems in General Relativity. I think, if I understand it well enough, that in GR space & time and or in space-time a coordinate system depends on locality, e.g. on an average distance between galaxies an the total amount...

hi. I am not a physicist and i have a question about quantum physics. If you shoot electrons towards a double slit and record what happens on the otherside. If you then burn the recording without ever watching it - would the electron act as if it wasnt being observed?

Hello, I was wondering if diffraction could be observed even in humans, but I can't prove it. Which is the De Broglie wavelength of a human? Is it possible to observe diffraction when a human passes through a door?:rolleyes:

Hi, what is the highest redshift observed for any 'object' in the Universe? Also, is the Abell-lensed 'object' still viewed as a possible candidate (at Z=10) or have people further studied this lensed 'object' and determined its high redshift as an error? Thanks you.

Hi. I have a question that I suppose is related to the Lorentz transformation, but I think that this situation is more simple: instead of relating the position of a light source between two observers, how would one relate the time difference between when a light signal is actually emitted versus...

I am interest in see the derivation for the speed of light from maxwells equations, or other interest derivation base on it. I want to understand whatever "natural" phenonmen that could be explained by maxwell s equations.

There's a machine that uses a type of plastic material (reinforced Teflon) as a wear ring. The plastic rides on a highly polished metal surface and eventually wears out at which point the machine must be rebuilt. If the plastic and metal sliding surfaces are exposed to bone dry (ie: no water...

Let says there's a starting point A. Two observer, B and C travel from point A in opposite direction with 90%c. How can we calculate the speed of observer C as observed by observer B?

Hey, I've got a question which I hope you guys can help me with. It is observed that Mars is somewhat brighter when in opposition (ie. sun- Earth - Mars in that order) that at other times. How can this be explained using a) The Ptolemaic model and b) The Copernican model of the solar...

A convex lens is placed on a flat glass plate and illuminated from above with monochromatic red light. When viewed from above, concentric bans of red and dark are observed. What does one observe at the exact center of the lens where the lens and the glass plate are in direct contact.

I remember vaguely hearing about gravitons being observed in some university in June. Did this really happen and can anyone give me a link or some details about the discovery?

If a beam of electrons pass through a plane where the potental energy abruptly increases but not enough to classically stop the electrons, some of the beam will reflect. Was this affect, or anything like it, ever observed before it was explained by the wave model?

why does vanadium have maximum observed oxidation state of +5 while for Co the maximum observed oxidation state is +3? why are solutions of chromium(2) acidic? :confused: :confused:

Is it possible to build a logical argument on the following line? 1) The force of gravity can only be observed between two or more bodies. 2) The claim that a single body has a gravitational field is purely theoretical; it cannot be observed. 3) If the only demonstrable gravity force is a...

Scientists have detected a flash of light from across the Galaxy so powerful that it bounced off the Moon and lit up the Earth's upper atmosphere. This "giant flare" was the http://www.everything-science.com/index.php?option=com_content&task=view&id=111&Itemid=2 ever detected from beyond the...

Hello, My first post on this forum, so please be gentle :smile: I have a paper I have to write on ANYTHING physics related for my physics class. First, a little info on my class. I go to ITT tech, so it may be considered 12 grade instea of 13 and up. Anyway, for my paper, I decided to...

The final conversatation between Doc Al and Russ_Watters in post 78 in the Speed of light thread went as: Reading this last post led me to question whether the conversation between Doc Al and Russ_Watters ought not be left unanalyzed. I had finished reading the entire thead earlier and began...

say that.. you shoot a really strong light facing towards space from earth, as the light travels in space it would lose energy and start to disappear. but before it all disappears, what if you use a really strong telescope pointing at the direction that you shot your light into space? would...

I was wondering if an expert in quantum physics can clarify a couple of things for me. I read this in the Wikipedia: This seems to suggest that are at least five different interpretations of quantum mechanics, each one the result of eliminating one of the five properties listed above...