Strings Definition and 523 Threads

How do I use Python to extract all text that comes between a recurring set of unique strings? Example: ABC;the red dragon;123, ABC;the blue dragons;123 ABC;the black dwarf;123, ABC;the gray elves;123 ABC;fantasy characters;123, ABC;winged balrogs;123 I want to parse through a large text file...

Homework Statement Homework EquationsThe Attempt at a Solution I tried to find constant k f = k ##\Delta##x 1/2 * 9,8 = k * 0,1 k = 49 N/m is rubber string the same as spring? Ep + EK at 0,1 meter = Ek + EP at 0,3 m 1/2 k x^2 + 0 = 1/2 k x^2 + 1/2 mv^2 v^2 = 2*49(0,08) v = 7*0,4 = 2,8...

Homework Statement A grid made of ropes is suspended by its four corners with strings tied to four different points on a building. Three of which are fixed and fourth is attached to a pulley which is in turn fixed to the building. Given data : Grid mass is 25 kilogram suspended at a height of...

If you have a rectangular box connected on 3 sides with strings, and you hold all the strings together at a point, with your hand; then you put a weight in the center of the box, which is open, would the tension on the strings differ than if you put the weight at a corner. Please describe it to...

Homework Statement In Figure 5, the two strings attached to the mass are fixed to the ceiling and the wall, respectively. Determine the tensions in the strings. Figure: http://i.imgur.com/jbTo1Nnh.jpg Homework Equations Please look below. The Attempt at a Solution Ceiling ##= 37^o## Wall ##=...

Homework Statement Consider the collection of all strings of length 10 made up from the alphabet 0, 1, 2 and 3. How many of these strings have weight 3? How many have weight 4? How many have even weight ? Homework Equations Combinations formulae The Attempt at a Solution Let me explain what...

Hello! I'm just having trouble understanding the logic about tension in strings. m = 5[kg] v = 2.8 [m/s] g = 10 [m/(s^2)] String in massless and air friction is negligible The question is what the tension in the string is when the ball is in the bottom position. My reasoning is that the...

Homework Statement A guitar string with 0.60 m and 0.012 of mass vibrates with frequencies that are multiples of 109 Hz. Approaching to the string a tuning fork of 440 Hz we verify beats between the sound signals of the string and the tuning fork. Calculate the time interval between consecutive...

“If the weak gravity conjecture is right, loop quantum gravity is definitely wrong,” said Nima Arkani-Hamed, a professor at the Institute for Advanced Study who co-discovered the weak gravity conjecture. source...

Hello, I would really like a book like Susskind's "An Introduction To Black Holes, Information And The String Theory Revolution: The Holographic Universe" but not so condensed. If you have anything to suggest please do so. Also, if you know of any book that contains any part of the above book in...

Homework Statement Question: (With the following definitions here: - Consider ##L_0|x>=0## to show that ##m^2=\frac{1}{\alpha'}## - Consider ##L_1|x>=0 ## to conclude that ## 1+A-2B=0##- where ##d## is the dimension of the space ##d=\eta^{uv}\eta_{uv}## For the L1 operator I am able to get...

Homework Statement Question: (With the following definitions here: ) - Consider ##L_0|x>=0## to show that ##m^2=\frac{1}{\alpha'}## - Consider ##L_1|x>=0 ## to conclude that ## 1+A-2B=0## - Consider ##L_2|x>=0 ## to conclude that ##d-4A-2B=0## - where ##d## is the dimension of the space...

I was supposed to write a program that has a while loop in which two people, person1 and person2 input a string. The program runs the loop until one of the people inputs "it's over". At that time the program should exit and print out the correspodance between these two people while they were in...

Homework Statement I have to create a program that dynamically allocates a string and uses up no extra space (The string takes up as much space as it needs to),checks if entered string is 'please stop this', if it is then the prgogram exits and if it isn't then it continues, it makes a copy of...

Hello, I am new to this. As I understand it, the difference between the quantum field theory and string theory is that in the former, physical field is considered as the fundamental reality, while in the latter it is believed that everything comes out of strings. My question is, by everything do...

Homework Statement There is a uniform slender bar which is suspended by two light inextensible strings and hangs in equilibrium. (if the mass and length of the bar are m and 2b ) Now, someone slightly knocks one end to make the bar rotate around the vertical axis with initial angular velocity...

One of my professor's assignments is proving particularly tricky for me. It reads: "Write the method public static void sort(String[] a) that sorts the array a in increasing order. The method must be a short recursive program. Do not use quicksort or merge sort. It should be a lot...

If strings are one dimensional objects and they make up every particle that we know of then there is no second or third dimension. There are only one dimensional objects that seem like they are three dimensional objects because they spin as they move through space.

1. The problem statement, all variables, and given/known data Suppose a block is suspended by two strings, one, T1, is anchored at 30 degrees to the horizon, the other, T2, at 60 degrees to the horizon. If the block weighs 100 kg, what is the tension in the two strings? Assume that: The...

Homework Statement String A is stretched between two clamps separated by distance L. String B, with the same linear density and under the same tension as string A. String B is stretched between two clamps separated by distance 4L. Consider the first eight harmonics of string B. For which of...

For a string in string theory, Energy = string tension * length So I'm wondering if it can increase its length with increasing its energy.

In string theory, if we have NN BCs along ##X^i, i = 1, \ldots, n-1## and DD BCs along ##X^a, a = n, \ldots, 25## then you get, from ##\alpha^{i,a}_{-1}|0,p\rangle ##, ##n## massless vectors and ##24-n## massless scalars. I understand that for the first excited level, ##M^2=0## and so we have...

Homework Statement How many strings of four lowercase letters have x in them? Homework EquationsThe Attempt at a Solution It seems that there are two ways of doing this. First, there are four ways to choose where the x goes, and then there are 25^3 number of ways to choose what the other...

Homework Statement A mass m is suspended by a light elastic string. When the mass remains at rest it is at a point 0, which is a distance a + b below the point from which the string is suspended from the ceiling, where a is the natural length of the string. The mass is pulled down a distance h...

When I was 6 or 7 I decided to make a bow and arrow one day. I had never seen or handled one in real life, but it was intuitively obvious to me from TV that they way to do this was to tie the ends of a stretched rubber band to the ends of a stick. This would have worked, after a fashion...

Homework Statement Two balls with masses m1=0.3 kg and m2=0.7 kg are connected by massless strings with lengths L1=0.2 m and L2=0.26 m, as shown. The arrangement of strings and masses rotates at constant angular frequency ω=57.6 radians/s around a fixed pivot point. Find the two tensions...

Homework Statement Two strings are stretched tautly parallel to each other. The length of one is L1 and the length of the other is L2(>L1). When both are simultaneously made to undergo fundamental vibration, beats can be heard at a frequency n. The waves in both strings travel at the same...

This is about the legitimacy of a possible operation. Take 0.999999... The operation is defined like this: 1) identify the insertion position with respect to the decimal. in this example we choose "3" as in the third position, 0.999999... 2) from the insertion position, inclusive, to the...

Hi, the question is obvious from the title. I am looking for the names of the top 30 schools in North America for research work in string theory and quantum gravity. Any feedback will be very helpful.

Homework Statement Hi all, I have solved these problems just wanted to see if it's all ok problem 1: a trolley starts at the lowest point of a diagonal plane with a 20m/s speed. Its acceleration is 4m/s^2 going downhill, the trolley goes up then slows until it reaches 0 speed and then goes...

Hi all! I have a question regarding the principal difference between QFT and string theory according to popular accounts. It is said that QFT deals with point particles leading to the well-known infinities in calculating the transition amplitudes whereas in string theory the interaction is...

Is it just me or are the videos at Strings 2016 unwatchable? They start and stop and continually seem to buffer, as if the bandwidth is not sufficient. The organizers did not respond to my email. I don't see a way to download and view offline, and I can't tell anything about the streams, e.g...

Back when I was studying at Princeton University, J.A. Wheeler introduced me to Ed Witten while we were having lunch at the Institute for Advanced Study (IAS). I knew Feynman’s and Wheeler’s views on “String Theory,” and I had looked into it a bit as a field of research, but I couldn’t seem to...

Homework Statement Homework EquationsThe Attempt at a Solution Suppose tension in the left string mAM be T1 and tension in the right string mBM be T2 .When the particles cross each other then the angle made by string mA and mB with vertical is α and that made by AM and BM be β . The speed...

I'm not a physicist so forgive me if this is a bad/stupid question, but i was just wondering what the current thinking was on a couple of things. (From what I understand space-time is a bit like a matrix which spreads out over the universe - and also gives us gravity etc?) 1. Does space time...

Homework Statement When talking about an Atwood machine, a student states: Is the student correct or incorrect? Why? Homework Equations Tension = mg + ma The Attempt at a Solution This is how it is making sense in my mind, but correct me if I'm wrong. I am thinking that the student is...

Homework Statement Give combinatorial proofs of the identities below. Use the following structure for each proof. First, define an appropriate set S. Next, show that the left side of the equation counts the number of elements in S. Then show that, from another perspective, the right side of the...

Homework Statement From the equation of best fit, determine the wave speed, v, for your string. Homework Equations f=(v/2L)n The Attempt at a Solution So I am supposed to find the speed of a wave using that graph and data. Do I just take the slope and replace the (f/n) in the equation? I...

Is this correct? Strings are one dimensional objects that form circles (hoola hoops) that flip in certain directions as they move through space. The strings can collide with other hoola hoops and break, then reform into other hoola hoops with different properties.

Do we know enough of string theory to say that because a quark is more complicated, in the sense that the quark experiences four forces verses three for the electron and two for a neutrino, that in terms of string vibrations quarks will have more complicated vibration patterns than electrons and...

Question: Suppose you have a finite state machine that accepts only strings with an equal number of zeros and ones. Show that you can then construct a finite state machine that accepts only strings of the form 0^n 1^n, i.e., an arbitrary finite number of zeros followed by the same number of...

C=130Hz G=196Hz D=293Hz A=440 Hz The distance from the nut to the bridge is 58cm, the amplitude of the string vibration is 2.2mm Part A: What is the period (T) of the G string? Part B: What is the side to side velocity of the g string? (Think simple harmonic motion) Part C: The diameter of the...

Hey all. I've started to read and watch lectures on string theory. usually everyone starts with a classical relativistic particle action, and then goes to a classical relativistic string action. after they finish with the classical string they start the quantization process. my question is...

Suppose an object of mass m is hung in a steady state by two strings. One string makes an angle 60 deg. at the point of contact with the object with the horizontal line. The other string makes 45 deg. To find the tensions in these strings (T1 and T2) we take all Horizontal Forces or their...

Several of my students have pointed me to this video: http://bit.ly/1N1IGR8 Apparently the guy put his cell phone inside his guitar and took a video. My initial reaction was that it looked fake, because the time scale of the movement of his thumb seemed mismatched to the time scale of the motion...

Homework Statement So In this problem, I have two strings, one string pulls with pounds and is 30 degrees away from an imaginary line straight down of of the two strings and there are no variables or degrees given for the second string. The weight is 20 pounds. I have been looking at this...

55 Hi all, Hello, Racking my brains over this : If I have two semi-infinite strings (made of same material) - which are connected by a massless spring, and now I send a longitudinal wave along one string. Will the spring just pass on the wave to the other string or will it serve to...

Homework Statement An object with a mass of 18 kg is suspended from 2 cables as shown in the below diagram. The tensions in the cables are T1 and T2. a) Draw a free-body diagram for the object. (already solved) b) Find the tension in both ropes, T1 and T2. (already solved) c) If string 2 were...

How many bit strings contain exactly eight 0s and 10 1s if every 0 must be immediately followed by a 1?