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About the Ultimate Fate of the Universe International Journal of Innovative Studies in Sciences and Engineering Technology (IJISSET) ISSN 2455-4863 (Online) www.ijisset.org Volume: 5 Issue: 9 | 2019 About the Ultimate Fate of the Universe Rahul Singh National Library Kolkata, 700027, India 2.1) BIG BANG THEORY: It is a chronicle result of Abstract: There are different view-points about the observation of expanding universe. As American ultimate fate of universe. Some of them have emerged Astronomer Edwin Hubble (1929) observed that from the theory of ‘beginning of universe’ while, others galaxies are moving away .Which is correlated with are the consequences of modern discoveries regarding their Redshift, [6][7] This theory was standardize by fundamental particles. What should be the fate of the Lambda CDM model. This model (lambda CDM universe is the common subject of these theories. model) help to describe about the expansion of However, what will be the exact fate of universe remains universe and it is also a root support of big bang theory unanswerable. Some theories are relying upon explaining about expansion of universe. Lambda (ʌ) mathematical proofs while, others verify their denote cosmological constant (or anti-gravity conceptions by employing observational data. component in Einstein’s Relativity equation). Interestingly, the search for exactness is still in process. cosmological constant is a basic component to establish Keywords: Big bang theory, lambda CDM model, big equilibrium in expanding universe, and dark matter rip, dark matter. described as cold because it’s velocity far less than the speed of light at an epoch of radiation-matter equality. 1. INTRODUCTION However, lambda (ʌ) has push to expand and cold dark Universe is expanding with accelerating rate of matter energy to create matter.[8] expansion.[1] The consequence of expansion or The velocity of expanding universe: contraction will shape the fate of universe. Many theories proclaim that the present universe is a 푣 = 2푐 1 − 1 + 푧 −1/2 (1) transitional phase of the bubble universe. [2]The Where z= Redshift universe existed from very big bang. It might be self- destroyer or it may end as the result of other cosmic 푧 = 휆표푏푠 − 휆푐푚 휆푒푚 (2) happening. Many observations support existence of dark matter. These observations show that dark matter 휆표푏푠 = 표푏푠푒푟푣푒푑 푤푎푣푒푙푒푛푔푡푕 play a significant role in expansion of universe.[3] 휆푒푚 = 푒푚푖푡푡푒푑 푤푎푣푒푙푒푛푔푡푕 Upcoming results of particle physics experiment might 퐷 be brought a new perspective about fate of universe. & z = 퐻 For small distances (3) [4][5] The observational data approves the theory with 0 퐶 help of applied mathematics. However, the theories about the ultimate fate of universe are the Hubble law is a distinct proof of expanding universe. mathematical guess about the future of the universe. [9]According to Hubble law , the velocity of expanding About the theories related to ultimate fate of universe universe: in section 2, some mathematical results according to purposed theory in section 3, the observational data in 푣 = 퐻0푑 (4) section4, what should be the fate of universe more precisely in section 5, how mathematics help to Where 퐻0 = Hubble constant understand the exact fate of universe would be in section 6. All these equations are about calculation to determining the rate of expanding universe. The 2. RELEVANT THEORY ABOUT THE FATE OF homogeneous and isotropic universe is expanding with UNIVERSE an accelerating rate of expansion.[1] [10] The result of With the time, discoveries make us more informed expansion the temperature of universe will have been about what is going on throughout our universe. getting down, as universe achieving maximum size of Different theory gave us different view with their universe .Consequently two possibilities emerged to respective conception. And the results of on-going deciding the ultimate fate of universe: experiments extract more efficient theory out of them. i). Big crunch or Bigfreeze: One emerging possibility Here I would like to present those theories, which from big bang leads to big crunch, big crunch is a make our understanding more clear about the fate of consequence of maximum expanded universe. When universe. the density of expanding universe highly decreases subsequently the metric expansion of space eventually reverse, consequently universe collapse. That © 2019, IJISSET Page 41 International Journal of Innovative Studies in Sciences and Engineering Technology (IJISSET) ISSN 2455-4863 (Online) www.ijisset.org Volume: 5 Issue: 9 | 2019 phenomenon will have been producing a unified black experiment. Here I am trying to present all relevant hole &big crunch singularity. [11]The other possibility theory about ultimate fate of universe with is big freeze, as big bang lead expansion the matter observational and experiment evidence very briefly. density of universe decrease subsequently the temperature will be getting down. The matter density 3 MATHEMATICAL INTER PRETATION of universe became more than the critical density. The Now I am trying to show some mathematical universe started to contract and result would be big interpretation, which are supporting with some extant crunch, or after expansion going on and on, The to the given theory about the fate of universe. temperature of universe will be continuously decrease, the consequence would be big freeze. so fate of 3.1) Future Expansion of the Closed Universe: If the universe depend on the origin (big bang) and the way universe is closed, then the total lifetime of the of expansion. [12] universe, from Big Bang to Big Crunch, can be relatively short in comparison with the characteristic time scales 2.2) Big rip with help of dark matter: Big rip theory of many of the physical processes. For a closed universe was proposed in 2003. According to the theory, scale with density parameter Ω0> 1, the total lifetime 휏푈 of factor of universe will become infinite in finite time the universe can be written in the form: with its all distances in universe.[13] It is a possibility 3 − −1 which depend on the ratio of pressure and energy 휏푈 = Ω0 Ω0 − 1 2휋퐻0 , (7) density: 2 푡푟푖푝 − 푡0 ≈ (5) 3 1+휔 퐻0 1−Ω푚 Where퐻0 is the present value of the Hubble parameter [22]. Notice that, by definition, the age 휏푈 → ∞ as Ω0→ Ρ 휔 = (6) 1. Current cosmological observations suggest that the 휌 Hubble constant is restricted to lie in the range 50 – −1 −1 −1 100 km 푠 Mp푐 [23], and hence the time scale 퐻0 is Where P is pressure and ρ is energy density andΩ푚 is restricted to be greater than ∼ 10 Gyr. Additional density of all matter in universe. If the value of ω is observations in [24].Suggest that Ω0< 2. Using these closer to -1 then denominator is to be zero and the results, we thus obtain a lower bound on the total further big rip will be fate of universe.[14] lifetime of the universe: According to the latest cosmological data available 휏푈˃20휋 퐺푦푟 . (8) .there is highly uncertainty in the value of ω, that what is exact value of ω˂ -1 or ω= -1 or ω ˃ -1. [15] [16] In terms of the time variable η, this limit takes the form 2.3) Big bounce theory: in the theory of big bounce, 휂푈 > 10.8 . (9) the present universe is a phase of expanding or This limit is not very strong – if the universe is indeed contracting universe. This theory explains about the closed, then there will be insufficient time to allow for expansion, as big bang come subsequently after big many of the processes we describe in this paper. crunch. Some observations support the theory such as ULAS J1342+0928. See [17] Other evidence with the We also note that a closed universe model can in supporting data. See[18] [19] these all observational principle be generalized to give rise to an oscillating data show the periodic expansion and contraction of universe. In this case, the Big Crunch occurring at the universe. So big bounce theory is also a relevant theory end of the universe is really a “Big Bounce” and about the fate of universe. produces a new universe of the next generation. This idea originated with [25] and has been subsequently 2.4) Big slurp theory: A new possibility about the fate considered in many different contexts [26]. of universe arises after the conception of Higgs Boson particle. [20] In which Higgs particles interact with 3.2) Tunnelling effect may be the future of other Higgs particle, this process channelize the universe: We next consider the possibility that the phenomenon of particle gaining mass more and more. universe is currently in a false vacuum state. In other Higgs particle would be bigger, denser and converted words, a lower energy vacuum state exists and the into ultra Higgs field. [21] One after one every Higgs universe can someday tunnel to that lower energy convert into a big bubble of mass and they slurp the state. This problem, the fate of the false vacuum, was whole universe. However this process came up with first explored quantitatively by [27] and by [28]. another relevant theory about the fate of universe. Additional effects have been studied subsequently, including gravity [29] and finite temperature effects These all chronological conceptions about the ultimate [30]. fate of universe are successful corrections in the idea of very big bang of universe. It is very difficult to say that To obtain quantitative results, we consider an which one is more relevant than other one. Some of illustrative example in which the vacuum energy them are leading experimental observation while density of the universe can be described by the others of them are result of some observational dynamics of a single scalar field. Once a field © 2019, IJISSET Page 42 International Journal of Innovative Studies in Sciences and Engineering Technology (IJISSET) ISSN 2455-4863 (Online) www.ijisset.org Volume: 5 Issue: 9 | 2019 3 configuration becomes trapped in a metastable state 0.5 < 푆4 < 3 × 10 .
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