Observed Definition and 195 Threads

Homework Statement Transitions between n=109 to n=108 have been observed in highly excited helium atoms and in this case the Bohr model is a valid approximation. Why is this? Homework Equations N/A The Attempt at a Solution I'm having some problems with this question and it probably comes...

Is this a ground breaking observation or does it agree with other observations? atures and the Wing-Ford band, presented in a recent paper. arXiv:1610.03854 [pdf, ps, other] The observed spatial distribution of matter on scales ranging from 100kpc to 1Gpc is inconsistent with the standard...

Can someone tell me that in bcc lattice why xrd 100 peak does not appear?

Homework Statement This is not really a homework or coursework question, but might be of interest to readers of this forum. It concerns what I have viewed on two separate occasions which baffles me. The setup was different it the two instances, but there are similar elements in both. In both...

what is the direction of velocity observed by fish when man flying from air to water?

Would it be possible for me to be anywhere in the universe and have a flashlight in hand and watch the beam of light move from point A to point B? If I was on a planet with extreme gravity (and could live) would I be able to watch light move? What if I was on the edge...not quite over the...

I have a model in which, for each store, predicted revenues are perturbed by a multiplicative shock: R = e^\eta r where r is predicted and R is observed. \eta is mean zero. I can find \eta as follows: \ln( r) - \ln( R) = \eta . I'm summing the squares of the \eta's. However, there are...

It seems to me that you would have to place two plates so close together and perfectly parallel for the effect to be visible. Correct me if I am wrong.

I have heard before that for every 1 billion antiparticles there are 1 billion and 1 particles of normal matter. Has this been observed directly or just predicted? Have we only observed antimatter through its creation on earth?

To me, it seems that with our current technology it would be difficult to observe the speed of gravitational waves. Can anyone correct me if I am wrong?

The following is taken from page 101 of Warren Siegel's textbook 'Fields.' Another example is quantum mechanics, where the arbitrariness of the phase of the wave function can be considered a symmetry: Although quantum mechanics can be reformulated in terms of phase-invariant probabilities...

Forgive me if this is the wrong place to ask this, but I am trying to do a mental exercise to understand time dilation relative to an observer's frame of reference. In my though experiment I am on a space station and someone is coming to meet me here. GST or Galactic Standard Time is always...

The problem statement, all variables, and given/known data: Assume that the radial velocities vr of galaxies, at the present time, are given by Vr=H0*r, where H0 = 65 km/(s*Mpc). However, we do not observe the present distances of galaxies, but the distances they had when light left them...

Homework Statement For a modern physics class, has to do with relativity In a lab experiment a muon is observed to travel 800 m before disintegrating. The mean lifetime of a muon is Tau = 2E-6 s A muon's travel distance at the speed of light is x = tc = 0.66 km Earth's atmosphere is x = 100 km...

I understand that neutrinos are emitted when supernova explode. I presume that there are quite accurate models that predict the energies of those neutrinos at the time of emission. Has the phenomenon of redshift been observed when those neutrinos are subsequently detected?

Homework Statement Let's say you want to find the minimum and maximum observed frequencies of light observed on Earth from the sun, when considering the Earth's motion around the sun. How would you go about doing this if you assume Earth takes time X to complete a revolution around radius R...

Because of the enormous mass of top quarks, they decay before hadronizing. But this doesn't explain why the top quarks are only quarks can be observed as bare quarks. If you look into any unhadronized quark in the time interval in the order of 10^-25 seconds, you must be able to observe it as a...

In afshar's experiment, it shows that the single photon goes through only one of the slits and produces an interference pattern. How is this possible? In this experiment, do we really know which slit the photon went through?

Let $ABC$ be a right angled triangle, where the right angle is at $A$. Construct squares on $AC$, $AB$ and $BC$ as shown. Let $P$ be the point of intersection of $BK$ and $FC$ (Note that $P$ is not marked in the figure). Then I conjecture that $AP$ is parallel to $BD$.What I tried:By obsercing...

Hi Folks-I am interested in knowing whether, in actual practice, people on Earth would see their 99% of c colleagues moving around in fast forward motion and if the reverse would be true from the vantage point of the relativistic astronauts who are moving away from earth. I suspect that since...

been answered numerous times i guess but i couldn't find it. i am an ignoramus. if spaceship doing 0.9c shines light forward we - from another inertial frame - see that light as proceeding forwards at 0.1c, do we not? But 'they' see it as proceeding forwards at c. fine. But if they shine a...

Has the Hawking radiation ever been observed from bodies like black holes or in laboratory? From what I saw, it hasn't... 1. What are the difficulties? 2. Why are we using Hawking Radiation in some reasonings, since we haven't observed it really happening?

Recently we got to watch G2 as its orbit took it around the black hole at the center of the galaxy. This showed a visual change in direction along with a corresponding redshift to blue shift change on a relatively short timeline. It was really a great event. Binary stars exhibit the same...

When an object is flying to the Earth and it's increasing it's speed through gravity, does a remote observer see this increase of speed too, or will he see the object moving at a constant speed? And another question: Is there any time dilation by the remains of an object that hits a planet...

In general relativity we have c^2ds^2 = c^2dt^2 - dx^2 -dy^2-dz^2. From this we can derive the not commonly used equation: (c\frac{ds}{dt})^2 + (\frac{dx}{dt})^2 + (\frac{dy}{dt})^2 + (\frac{dz}{dt})^2 =c^2 \qquad\qquad\qquad (1) I think this is the "velocity" squared of an object relative to...

Assume observer is located on the surface of the Earth with a small amount of time dilation due to gravity. There are two beams of light moving approximately parallel to the surface of the Earth at some moment in time and the reflection of the beam off some objects back to the observer is being...

I thought this was pretty neat: http://www.sci-news.com/astronomy/science-hvgc1-hypervelocity-star-cluster-01897.html http://arxiv.org/abs/1402.6319 From the abstract: We report the discovery of an object near M87 in the Virgo Cluster with an extraordinary blueshift of -1025 km/s...

Hello, I have been trying to find an equation to represent the observed angular velocity of any object traveling in a straight path x and y distance away from where its being observed, along with the moving objects velocity. My problem is that I am getting a differential equation that in its...

Is there an absolute sequence of events in the universe- independent of observation? It seems like so much emphasis is put on our delayed observations rather than what is actually happining in Reality. As I read through the forums, it almost seems as if people do not believe that there is an...

There are only two frame moving relative with each other at certain velocity. One frame see the other going right and the other to the left. Isn't it contradict that each see the other time running slow and both are correct? And this isn't the case , where one twin leave Earth and each see...

http://www.bbc.co.uk/news/science-environment-25849871 Herschel space telescope press release: http://sci.esa.int/herschel/53125-herschel-discovers-water-vapour-around-dwarf-planet-ceres/ Abstract of scholarly article published in Nature...

When I had a school tour to A water park, there I observed that when a heavy boy used to slide down a water slide(and stop at β), he used to go further than where the ligher boy used to stop after sliding(α). But the friction will act more on Heavier then why is he going further?

I was wondering if there are any theories that show how much mass the higgs field gives to each particle and why? I am specifically wondering about the observed masses for each particles rest mass. Does the higgs mechanism give mass in quanta, and if so is there a reason for the amounts?

Hello, Just discovered this forum as I'm so intensely curious about this question I sought out just such a place! I'm currently designing a circular patio using 6-in square blocks in concentric circles. While using a combination of Excel and Adobe Illustrator, I uncovered something...

Hello! Are the transformations such as time dilation, length contraction and relativistic mass just observed ones or real ones? Thank you.

As usual, the interpretation is still unclear, but I think it is an interesting effect. LHCb studied the angular distributions in the decay ##B^0 \to K* \mu \mu## and presented the result at EPS2013. In one variable (called P'5) in two bins, a large deviation was found (3.7 sigma in one bin)...

Sure we all know it happens at the core of the Sun, but the half life for a proton there is a billion years because p + p -> D + e + v is so unlikely A thermonuke bomb using light H would give no extra energy at all above the fission primary. Even the Sun only gives a few watts for bomb...

An object is an isotropic light emitting source and the object moves very near the speed of light c. I am an observer on a planet without an atmosphere and I see the path of the object as a line that is perpendicular to the normal from the planet's surface where I am standing. Now take a line...

I haven't studied quantum physics academically and I have no understanding of it mathematically so forgive me if my questions are strange, nonsensical or erroneous. For instance in the double slit experiment when we attempt to observe the object going through a slit then the diffraction...

What are the strangest known nuclei? Specifically, have any nuclei with strangeness over 3 been seen? Are there any known charming or beautiful hypernuclei? Considering that Be-8, with half-life 10-16 s is a well described nucleus, the 10-12...10-13 s lifetime of charming and beautiful...

From an experimental study I've found that alpha helices are formed more often than beta sheets when the temperature is low, but when the temperature increases the beta sheets becomes more common. I'm trying to figure out why. As temperature increases, the outer hydrogen bonds of a structure...

http://arxiv.org/abs/1211.3663 CLASH: Three Strongly Lensed Images of a Candidate z ~ 11 Galaxy Dan Coe et al (Submitted on 15 Nov 2012) We present a candidate for the most distant galaxy known to date with a photometric redshift z = 10.7 +0.6 / -0.4 (95% confidence limits; with z < 9.5 galaxies...

Are there any known examples of colliding stars? has the phenomena ever been observed? tex

Homework Statement During a hurricane, a 1,200 Hz warning siren on the town hall sounds. The wind is blowing at 55 m/s in a direction from the siren toward a person 1 km away. With what frequency does the sound wave reach the person? (The speed of sound in air is 330 m/s.) (A) 1,000...

Today i was heating a bowl of soup..the intensity of the flame of the gas stove was quite high.. i observed that the bowl got burnt and when it cooled down a bit, i observed a band of colours..blue was the most prominent..i noticed the presence of violet, yellow and orange too.. I wish to know...

With CERN's Large Hadron Collider being in the news recently, I began to think of a question that bothered me for years about particle accelerators. It is well known in physics that mass increases as velocity does (Special Relativity if I'm not mistaken), so if these particles in the LHC are...

Hey Guys, I continue to get mixed messages about the nature of electron behaviour during the double slit experiment. I have heard the term observation used to describe an interaction with the electron (Obviously necessitating a change in it's behaviour to facilitate the ballistic outcome)...

Quantum Confusion -- "Does not exist until it's observed" and age of universe Hi. I ran across this: http://physics.jamesbaugh.com/quanta.html QUOTE: "It is a problem of assuming values of properties are "out there" independently of the acts by which the values are determined. The...

Hi. I would like to know if the results of the observations of electrons passing through double slits needs to be observed by a person for the electrons to act like theyve been observed? Or, is the equipments observation of the electron is enough for it to act like its been observed...

One of the major concerns in any Cosmic Microwave Background (CMB) anisotropy analysis is to determine which fraction of the observed signal is due to some foreground contaminant. Two sources of foreground contamination have been firmly identified: the diffuse Galactic emission and unresolved...