Existence Definition and 571 Threads

  1. O

    Existence and Uniqueness of a solution for ordinary DE

    I just don't understand the idea behind it. I hate it when they throw these theories at us without proofs or elaborate explanations and just ask us to accept and applym mthem. Anyone care to enlighten me?
  2. W

    Maximum interval of the existence

    Homework Statement Suppose f(t,x) is a continuous vector valued function on \mathbb{R} \times \mathbb{R}^n. If f is locally Lipschitz with respect to x with the property that \|f(t,x)\| \le C \|x\| for some positive constant C > 0, then prove that the maximum interval of the existence of the...
  3. L

    Algorithmic information theory and the existence of a Unified Field Theory

    I have recently been studying Gregory Chaitin's "algorithmic information theory" for a school project. It describes the complexity of mathematical objects by the size of the smallest Turing machine program capable of computing them (in bits). It also defines a "random" object as one with an...
  4. D

    Does vacuum energy rely on the existence of matter?

    From what I understand, vacuum energy is a form of energy that exists in freespace, even when completely devoid of matter. So, I have two questions: 1. Can vacuum energy exist if there were no matter anywhere in the universe? 2. If so, where does this vacuum energy come from?
  5. E

    Existence of virtual particles

    Are we sure about the existence of virtual particles?
  6. S

    Haag's Theorem, Perturbation, Existence and QFT.

    Hello, I just reading and learning QFT and there is something I've been wondering, hopefully somebody here can help me. Let's say we have an interacting Quantum Field Theory, such as Quantum Electrodynamics if we want to compute an amplitude such as two electrons scattering off each other, then...
  7. L

    What is existence and what will it mean to exist ?

    What is "existence" and what will it mean to "exist" ? What will it mean that I (eventually) does exist ? What will it mean that something outside me exist as observed by me ? What will it mean that something outside me exist as I does not observe it ? What is then "exisistence" ...
  8. marcus

    Wiltshire casts doubt on existence of dark energy

    Wiltshire casts doubt on existence of "dark energy" Wiltshire is a minority voice in cosmology, but one worth listening to. Speculation about a "dark energy particle" would be in vain if the appearance of acceleration can be traced to classic GR effects, which is what he tries to do. Wiltshire...
  9. P

    Existence of the instantaneous center

    I would like to find a proof for the existence of the instantaneous center, and show that it only exists for velocity and not acceleartion. Anyone know where I could find this proof.
  10. V

    Quantum theory, consciousness and existence

    Hi everyone I'm currently readig Bruce Rosenblum & Fred Kuttner's book Quantum Enigma: Physics Encounters Consciousness and studying to be an NLP practitioner as well as practising tai chi. There are lot more parallels in these three areas than I imagined there would be. I have a few...
  11. N

    Seeking the truth behind existence of charge: An Intricasy

    According to Klein Kaluza theory of fifth dimension (followed by string theory), there is an elecromagnetic dimension in which every particle of Universe (in Dirac Vacuum) perform translatory and rotational motion due to which they drag the e-m dimension. Thus if any two particles are placed...
  12. T

    Proof of existence of a Jordan form?

    I have been recently introduced to the idea of Jordan form of a matrix, and I have attempted to prove it. However, there is one step that I cannot prove. If I can prove the step, then everything else is done. Let A be a m by m matrix with characteristic polynomial ch(x)=(x-\lambda)^{m} I want...
  13. D

    Proving the Existence of a Color-Matching Rectangle

    Homework Statement A plane is colored blue and red in any way . Prove that there exists a rectangle with vertices of the same color Homework Equations Its obviously true. The Attempt at a Solution I was thinking proofy by pig hole, but haven't quite figured it out.
  14. MathematicalPhysicist

    Existence question about matrix and ranks.

    i need to prove diprove that there exist matrices A1,A2,...,As such that rank Ai=1 for every i=1,...,s and A=A1+A2+...+As with rankA=10. my feeling this is not true, i thought trying to prove this by ad absrudum, let us assume that they exist, then the rows of Ai are scalar multiple of one row...
  15. M

    Existence of solution to Poisson's equation

    I'm reteaching electrodynamics to myself on a more rigorous footing, and I'm trying to prove to myself that setting the divergence of the vector potential is justified using a gauge shift. I could use the Helmholtz theorem to do this, but the problem with this from my perspective is that I...
  16. P

    RE: Thoughts on existence (& happiness)

    RE: Thoughts on existence (& happiness) Sorry I'm not sure if its o.k. to continue a thread, I just find this an interesting subject because it's such a basic question. What are peoples reasons for living from one day to another? Not only as individual humans but as a whole specie. I'm not...
  17. N

    Vote: Physical Existence Poll: 4 Options

    This poll presents these options "I experience life as a physical phenomenon" and "I experience life as a non - physical phenomenon" and will include the obligatory third option of "all of the above" and the 4th choice "I experience life in a way other than physical, non-physical and not...
  18. M

    Can We Ever Truly Perceive Reality as It Is?

    There are certain possibilities for the form of existence from my point of view but one of these possibilities seems to be really logical and sounds very likely to be true which is given as follows I'd be glad to receive your comments on this subject; Let’s imagine two astronomers traveled...
  19. O

    Can We Ever Fully Explain Existence?

    hello I'm new. I'm 27/m/ USA. I'm interested in trying to explain existence. i am hoping to start a thread where we all try. I've been studying and trying for a long time but have never shared my conclusions. so i guess i'll start ...hopefully we can all just keep adding on and reach the...
  20. M

    Urgent: Existence and Uniqueness theorem

    Greating my friends, I have just returned home today from heart surgery. I still feeling the effects of the operation, because I'm affried the hospital send me home a bit to early. But I have to have these questions finished before tomorrow. So therefore I would very much appreciate...
  21. F

    Does Non-Lipschitz f(x,t) Ensure No Global Unique Solution?

    Hi, For a first order Diff Equa. x'=f(x,t) and the IC: x(0)=x_0. with t from [0 to infinity) If f(x,t) doesn't satisfy the Lipschitz condition, can I say for sure that there doesn't exist a global unique solution? I think the answer is "no" but I am not sure. Can you all confirm...
  22. Unes

    Name of God The Source of our Existence

    In the name of God The Source of our Existence Civility Introduction Chapter I: Civility Chapter II: Adam and Eve Story of Paradise Chapter III: Moses Story is a Fiction Chapter IV: Christianity in Crisis Chapter V: A Plausible Philosophy of Soul...
  23. kreil

    Proving Existence of x2=b for b≥0 in R

    Prove that if b is greater than or equal to zero (b in R), there exists a non-negative real number x such that x2=b. I really don't know where to go. I think I need to modify a proof done in a class that I missed, so if someone could just give me a few hints I'll fill in the rest. Thanks Josh
  24. L

    Do These Integrals Always Exist Under Certain Conditions?

    Let be the integrals: \int_{-\infty}^{\infty}dx Cos(uf(x)) (or the same but a sine) and \int_{-\infty}^{\infty}dxe^{-ag(x)} Where "a" is a a>0 positive constant, u can be either positive or negative.. and g(x)>0 for every real x.. my question is will these integrals "always2 exist...
  25. M

    Existence is an Illusion – My Point of View

    Hello, I would be glad to know your point of view on the following idea of mine :smile: , I'll be happy to have links for or against this idea. Thankyou for giving the time ________________________________________________________ Whenever I start thinking about the existence of the...
  26. R

    Can anything truly exist without being measurable?

    Can we agree that "all existents can be measured" ? By existent we mean "an entity (thing) of a specific nature made of specific attributes". By measurement we mean "the identification of a relationship between an attribute of an entity and a standard that serves as a unit". Thus can we agree...
  27. W

    Ideas on Existence: Gravity, Light, Time & Beyond

    Just wondering a few wonders out (i don't have much knowledge about physics and stuff, just the basics, so don't expect me to not ask questions that don't make sense to some, or to know answers that should be obvious). Just too much thinking time on my hands. First, just wondering if a test...
  28. C

    What is the role of coexistence in the existence of matter and life?

    In studying physics and as much literature as I can possibly get my hands on I have come to a theory as to why everything from bosons and quarks up to conscience human beings exists. The simplicity of the concept suprised me but when I tried applying it to every level inbetween I can not find...
  29. C

    Is Our Existence a Reflection of Divine Consciousness?

    About a year and a half ago I came to the decision that I'm no longer christian. Since then I've been studying every source that has anything to do with our beginning. Its through my study of physics and cosmology that I've finally come to my belief in our origins. In the bible it says that...
  30. K

    What is "Existence" - Exploring Its Meaning

    The recent topic is about existence.I do not want the precise deinition.But, want to know clearly, what does it mean.
  31. W

    Existence of fringe effects with a capacitor

    I was surfing some old exam questions and I found a nasty one... They asked to prove the existence of fringe effects of the electric field at the edges of a plate capacitor, using Maxwell's laws. In class we always assumed the ideal capacitor without fringe effects so I'm having some kind of...
  32. U

    Need help with ODE and Existence and Uniqueness Thm

    Need help with ODE and "Existence and Uniqueness Thm" I'm currently helping my neice study for her exams and going though last years test there was this one question that I wasn't sure about. ------------- Considering the initial value problem, \frac{dy}{dx} = f(x,y) Where f(x,y) = (1+x)...
  33. P

    There is no point to our existence, and all life is disposable.

    I have a harsh realistic philosophy. I enjoy it too. I am a atheist, and do not believe in any "super natural power" such as a "God." I know that science has its laws and that we were created by some chemical process. Humans contribute nothing, nor is there anything to contribute too. The...
  34. Y

    Unanswered Questions of Existence: Seeking Answers

    i have some question and i hope i put this topic in the right thread.. >> is there any philosophy or science maybe that until now has not yet been discovered that could serve as an answer to the question about on how all things in the universe [including us] came into existence. For me i...
  35. mattmns

    Lin Alg - Eigenvector Existence proof

    Lin Alg - Eigenvector Existence proof (More of a proof ?, than eigenvector ?) Here is the question from my book: Show that If \theta \in \mathbb{R}, then the matrix A = \left(\begin{array}{cc}cos \theta & sin \theta \\ sin \theta & -cos \theta \end{array}\right) always has an...
  36. G

    Does Existence Exist? Exploring Nothingness & Beyond

    When nothing exists, nothingness exists. (Because I'm alive and we use words.) If so, existence exists. Is there a state where existence doesn't exist? Is there a state where nothingness doesn't exist? When I die, will nothingness continue to exist? When I die, will existence...
  37. T

    Proving Existence of a Cyclic Vector for T

    "Suppose V is an n-dimensional vector space over an algebraically closed field F. Let T be a linear operator on V. Prove that there exists a cyclic vector for T <=> the minimal polynomial is equal to the characteristic polynomial of T." (A cyclic vector is one such that (v,Tv,...,T^n-1 v) is a...
  38. L

    Possible experiment to determine existence of souls?

    My friend and I were having a discussion about human existence and sentience, and an interesting idea for an experiment came up. Suppose two genetically identical people of the exact same age and parentage were raised in two identical rooms separated from all living things. There are no...
  39. N

    Does the Cosmological Argument prove God's Existence?

    This is my first post here, so I appologise in advance if this is the wrong forum. Anyway, I was interested to see if this was a generally held opinion. My philosophy course didn't really go into much detail (alas, only Higher level (in Scotland)) I think that the cosmological argument goes as...
  40. T

    Proof: Sufficient condition for local extreme existence

    Let G \subset \mathbb{R}^{n}\mbox{ open } a \in G f : G \rightarrow \mathbb{R} f \in C^{1}(G) Df(a) = \overrightarrow{0} Then: (i) if D^2f(a) is positively definite, then f has local minimum in a (ii) if D^2f(a) is negatively definite, then f has local maximum in a (iii) if...
  41. S

    General and specific existence and uniqueness proofs

    Short question: Can anyone provide me with a nice synopsis of how to go about proving the "existence" of some object as often requested in math questions such as, "prove that X really exists and is unique"? In other owrds, in general, when presented with an "existence" question, is there a nice...
  42. A

    Exploring Reality: Is Existence Just an Illusion?

    The question of reality, existence and philosophy in general is (as most of us would agree on, I assume) based on human brain activity. We think with our brains, we process EVERY INPUT of information from this "existence" or "reality" or whatever you want to call it with our brains and generate...
  43. Y

    Searching for the Higgs Field: 95% Confidence of Existence

    Hello, For clarification because of the ambiguous situation in searching for & concerning the Higgs Field. It is with 95% confidence that the Higgs Field exists. Yet it has not been seen as of the end of 2005. I hope LHC/CERN will shed light on the subject. Anyone dealing or knowledge...
  44. T

    Impossible for Universe/Existence to be Random?

    is it mathematicly/statisticly impossible for the universe and existence (i'm talking from the moment of the big bang to when life first appeared) to have happened randomly? so many billions and billions of thing's had to happen just right from the big bang to when life first appeared without...
  45. G

    The Limitations of God's Power: Examining the Logic Paradox and Existence

    A common argument: Suppose God is all-powerful. Now, let God create a rock so heavy that God cannot lift it. Common conclusions: 1) But if God cannot lift it, then God is not all-powerful. 2) The rock cannot exist since it creates a contradiction. Thus, God is not all-powerful since...
  46. A

    Is existence faster than the speed of light?

    lets say theoretically you have a rope 200,000 miles long and it was pulled tighted with a person on each end one persons pulls the rope towards them instantaneously the rope begins to leave the other person wouldn't this conclude that something is faster than the speed of light?
  47. Z

    Nothingness: Examining Existence Beyond the Mind

    does nothing exist apart from my mind?
  48. H

    Existence and Uniqueness Theorem

    Can anybody help me with the proof of Existence and Uniqueness Theorems.
  49. S

    Existence of Virtual Particles

    As I understand it, according to the Copenhagen interpretation of QM, nothing can be said to exist until it is observed. I have also read that it is impossible to observe virtual particles in an experiment. How is it then that virtual particles can be said to exist?
  50. P

    Exploring White Holes: Existence, Properties, and Connections

    Hi, Do white holes exist? If not why not? If a white hole is the opposite of a black hole then it will have the following properties:- Black holes converge, localise or attract matter towards a point. white holes diverge, non-localise or repel matter. White holes should therefore be called...
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