Events Definition and 352 Threads

We see collision detector images showing a lot of curved lines radiating out more or less from the central area. We hear that literally thousands of scientists the world over process and resolve these images and get information from them. How is this done? How can the mass of a particle be...

Does probability apply to past events before determining the outcome? Does the probability of an undermined past outcome change to p=1 when the outcome is revealed to have occurred? Does the probability of a future event change to p=1 after it happens? I may have more questions, probably...

If there is a 5 percent chance of getting a particular result, and there are 15 of these events taking place simultaneously with the exact same probability, then collectively, what is the chance that one of these events will take place? For example, if 15 cars of the same make and model...

How to use Matlab ODE solver "events" to stop an integration I'm using Matlab's ODE solver (specifically ode15s) to solve a system of equations. The sum of the values of the equations eventually arrive at a steady state, but the time at which that occurs is dependent on several things, not...

I have a problem that is suppose to be very basic, but it's hard for me to understand. Problem: Two dice are thrown. Let E be the event that the sum of the dice is odd; let F be the event that at least one of the dice lands on 1; and let G be the event that the sum is 5. Describe the events EF...

Do nested quantum events prove the Many Wordls Interpretation of physics 1) First create quantum events that surround other quantum events like a photon path that circles a fissioning element, if the photon usually takes 100 times as long to reach the detector per each fissioned nucleus...

I am not sure if this belongs in General Relativity or Quantum Theory or just General -but here goes. First , I have to say that I do assume Space-Time to be quantized (since anything else seems too difficult!) and this is my question. I have often read that physicists have peered back...

Homework Statement One event is separated from another by a lightlike interval, can the first event have caused the other. Homework Equations The equations are not important. The Attempt at a Solution It all seems to boil down to the definition of an event, can you call the light...

Homework Statement S' moves at velocity 0.6c with respect to S, and x=x'=0 at t=t'=0. Two events are recorded. In S, event 1 occurs at x=0 and t=0, and event 2 occurs at x=3000m and t=4μs. At what times does S' say the events happened? Does S' see the events in reverse order from S? The...

Hi there! I'm working on a couple of problems regarding simultaneity. For one I'm given events X_a = (ct,x,y,z) = (2,1,-3,2) and X_b = (6,3,-1,5) I want to find out if there's a frame of reference where the events are simultaneous. I find the change vector X_b - X_a = (Δct,Δx,Δy,Δz) =...

Hello, The three clocks A, B and C is at rest in S frame. The clocks unsimultaneously change its frame from S to S'. The frame change events is simultaneous in S' frame. Now, clocks is moving in S frame and at rest in S' frame. I am struggling with this. The events on A clock displayed by...

Hi, I am trying to follow this paper: (arXiv link). On page 18, Appendix A.1, the authors calculate a covariance matrix for two variables in a way I cannot understand. Homework Statement Variables N_1[\itex] and [itex]N_2[\itex], distributed on [itex]y \in [0, 1][\itex] as follows...

Question: An urn contains 10 balls: 4 red and 6 blue. A second urn contains 16 red balls and an unknown number of blue balls. A single ball is drawn from each urn. The probability that both balls are the same color is .44. Calculate the number of blue balls in the second urn. My attempt I...

Let $A_1$, $A_2$, and $A_3$ be three arbitrary events. Show that the probability that exactly one of these three events will occur is $\Pr(A_1)+\Pr(A_2)+\Pr(A_3)-2\Pr(A_1\cap A_2)-2\Pr(A_2\cap A_3)-2\Pr(A_1\cap A_3)+3\Pr(A_1\cap A_2\cap A_3)$ My attempt: The required probability$=\Pr(A_1\cap...

Ok, I want to make sure I understand this correctly. Let's say I'm moving at 90% c and pass a light bulb that is at rest with another light bulb in the distance. In the frame of reference of an observer equidistant from the light bulbs, they flash at the same time that I my distance from each...

consider A and B particles synchronizing clocks. Immediately after that B flies off at high velocity at the same time A flashes light perpendicular to B's motion. It hits some target c. Now in A's frame the event happened after t_{a}=perpendicular distance/c. But in B's frame it happened after...

Please refer to the attached diagram The train moves in the direction B-A If the events seen in the ground observer simultaneously, it should be seen at A before B in the train In special case, the difference in times between A and B according to the train observer could be equal to the...

I'm trying to understand the causal structure of Minkowskian spacetime and I was wondering whether something can be said about the relation between the classification of events and curves. To clarify: for Minkowskian inner product \eta with signature (-+++), two events p and q can be timelike...

Let’s make the following experiment: A train moves in the direction B-A where A is the front end and B is the back end. There are 2 slits at both ends. Let us make 2 arrangements: 1) The source of light is put near the front end A so as to make the light signals reach A & B at the same time...

Probability ? How do you find the intersection of the complements of two negatively dependent events? I'm given P(a), P(b), and P( A intersect B), but I need to find the conditional probability of 'the complement of B given the complement of A'. I don't know how to find it. I thought I only...

Homework Statement I am stuck on this problem relating to permutations: The first part asks how many ways can 6 people be lined up. This answer, I believe is 6! = 720 ways. The second part: If 3 specific persons, among 6, insist on following each other, how many ways are possible...

Homework Statement During a winter season at one ski resort, there are two roads from Area A to Area B and two roads from Area B to Area C. Each of the four roads is blocked by snow with a probability p=.25 independently of the other roads. What is the probability that there exists an open...

Bag contains 9 blue balls, 3 red balls. A ball is selected at random, colour recorded and NOT replaced. A second ball is selected at random, colour recorded. a) Draw tree diagram (no problem). Part 2 a) Find probability second ball is red (no problem, 0.25) b) Find probability both...

Homework Statement events A(ct,x)=(1m, 2m) and B(ct,x)=(3m,4m) are separated in a lightlike interval. I need to find the velocity of a separate reference frame in which they BOTH occur at the same time. Next I need to find the velocity of the frame where they will occur at the same...

Hi guys, I'm learning about partition sets of the sample space. I understand that events form a partition of Ω when: 1) events are mutually exclusive from each other 2) union of events adds up to Ω My question is: how do can I determine if the events are mutually exclusive to each other...

When 2 objects A,B are moving wrt to each other (lets say @0.86c)then from frame A if local time is 10 years then time at B is 5 years. What does this mean?is it any event happening now in A(10 years) is simultaneous with the events happened in B when its clock ticked 5 years?

It has been a year for the history books. What were the major events of 2011? I put the Arab Spring, Libya, leaving Iraq, and getting Bin Laden, right at the top of the list.

Thought experiment: Say for instance that a Baseball game is being played out on a planet that is orbiting the outer edge of a black hole. You, from deep in space away from any gravitational source, are watching this game from a powerful telescope. The batter comes up to bat; the pitcher...

Registered events X in time interval t are distributed linearly n = n0 + bt. Find probability density function, then t = 10, n0 = 5 and b =2. Find average amount of registered events per day and Mean squared error. Find the probability to register an event per 5th and 6th days. What is the...

"Construct a sample space to show that the truth of this statement P(A\bigcapB\bigcapC)=P(A)*P(B)*P(C) is not enough for the events A,B,C to be mutually independent. Hint: Try finite sample spaces with equally likely simple events." So, my though is that I need to find a sample space with...

I am not sure if I am doing this correctly, so please check my attempt: I have four discrete random variables: G, H, J, L Say, I want to find P(H|J, G, L). Then can I write as P(H|J, G, L) = P(J, G, L|H)*P(H) = P(J|G, L, H)*P(G|L, H)*P(L|H)*P(H) Are those equivalent? I can't find an...

Show that an event A is independent of every event B if P(A)=0 or P(A)=1. **I was able to prove the first part of this problem that is that the events are independent when P(A)=0. However I am stuck on the part where P(A)=1. I have this so far: P(A n B) = P(A)P(B/A) =...

Homework Statement 2. Let a random experiment be the cast one “six-sided” die and one “four-sided” die. (a) Give an example of two independent events and justify your answer. (b) Give an example of two dependent events from this sample space and justify your answer. Homework Equations...

This is not homework problem, but I am using a problem from Elementary Modern Physics by Weidner and Sells as context for my question. It reads "A star is moving away from the Earth at 0.60c as measured in inertial system S, at rest with respect to the earth. At time t=0, when the star is 1.0...

as we increase our speed, time goes slow for us, does it mean we will be left behind in times only or as time goes,do we observe the same event that has been observed by those who were ahead than us bcoz of their speed slower than us. or it depends what happens at our present time. Also how...

1) A1 A2 be two events, show that P (A1 ∩ A2) ≤ P (A1) . P (A2) 2) show that P (A1 ∩ A2 ∩ ... ... An) ≤ P (A1) . P (A2) . ... ... ... ... P (An) 4) show that P (A + B) + P (/ A + / B) = 1 I have problems with these exercises. I don't know if I copied them wrong. thanks

CERN "Zen Events" - 1985 Starting from 01:43 in the following video, mysterious CERN "Zen events" are discussed being particle collisions with a distinct unbalanced/off-track dispersion patterns. This programme was filmed in 1985 and the video explains that these collisions could not be...

Are they going to shoot themselves into the foot by doing so ? http://www.scientiaweb.com/2011/06/16/new-iphone-technology-prevents-capturing-live-events/...

Hi, I keep seeing this come up A1 ⊇ A2 ⊇ A3 ... is an infinite decreasing sequence of events. Prove from first principles that P(intersection of Ai from i=1 to infinity) = Lim P(An) as n--> infinity All i can think of is that since each is a subset of the preceding, then A1 ∩...

Few things happened recently: 1) About 100 or so drone attacks per year killing many terrorists as well civilians 2) A CIA contractor (Mr Davis) was bailed out from legal punishment after he murdered someone in Lahore (http://www.bbc.co.uk/news/world-south-asia-12305049) - he got out after...

Homework Statement Show -0.25 <= P( X \cap Y ) - P( X )P( Y ) <= 0.25 for any events X, Y Homework Equations P( X \cap Y ) = P( X )P( Y | X ) Bayes' theorem Anything I missed? The Attempt at a Solution Obviously if X and Y are independent P( X \cap Y ) = P( X )P( Y )...

Well I'm sure a lot of us have seen websites predicting the end of the world from solar flares causing earthquakes. I'm a physics grad student and with my limited knowledge I have the impression that all such theories are pseudo scientific. But still I want to ask the question. It is...

Hi, I am new to this forum so hello to everybody. I have this problem to solve: Homework Statement Q is moving away from P at speed 4/5 c. After 3 years (in Q's frame of reference) he turns around (assuming that turning takes no time) and is moving back to P at speed 4/5 c. What are spacetime...

What triggers the onset of an el nino event? Are my conclusions listed below reasonable? The southward conduction and flow of cold air and water from the arctic region in the north are inhibited by local air and sea currents in and around the arctic warming the pacific ocean around indonesia...

if you have a sequence of events {A_1, A_2, ...} then an expression for the event that "infinitely many A_i's occur" is: U(n = 1 to inf, U(m = n to inf, A_m) ) but wouldn't U(n = 1 to inf, A_n) also satisfy this?

Homework Statement Show that for 3 events A, B, C, the probability P of the intersection of A, B, and C is greater than or equal to P(A) + P(B) + P(C) - 2. aka: P(A intersection B intersection C) > or = P(A) + P(B) + P(C) - 2 Homework Equations N/R The Attempt at a Solution Use...

I never understand the difference between 'Equally Likely Events', 'Mutually Exclusive Events' and 'Exhaustive events'. I also get confused in calling an event to be of more than one type. I would be grateful if someone explains it clearly giving examples.

I'm having difficulty time of trying to figure out answer. Question: P(A^c U B) = 0.6 P((A^c U B^C) = 0.8 Find P(A) ? Sol: P(A^c U B) = P(A^c) + P(B) - P(A^c Intersection B) P(A^c U B^c) = P(A^c) + P(B^c) - P(A^c Intersection B^c) 0.6 + 0.8 = 2*P(A^c) + 1 - P(A^c) <==== HOW ? P(A^c)=0.4...

I've written a scifi short story for a contest on the theme of environmental disaster, and I want to check the plausibility of the chain of events that occurs in the story. 1. It opens with a spill of massive quantities of methyl and phenyl isocyanate into a bay area on a planet in the...

I'm guessing this requires some difficult and monotonous math so I figure if it has been done, it required expensive computing equipment. But, does anyone know of any info or have participated in a computer astrolabe program that has ran the numbers backwards as to the position of planets and...