Marketed By :  LAP LAMBERT Academic Publishing   Sold By :  Kamal Books International  
Delivery in :  10-12 Business Days

₹ 3,651

Availability: Out of stock


Delivery :

5% Cashback on all Orders paid using MobiKwik Wallet T&C

Free Krispy Kreme Voucher on all Orders paid using UltraCash Wallet T&C
Product Out of Stock Subscription

(Notify me when this product is back in stock)

  • Product Description

Unified Dark Matter models aim to describe thedynamical properties of Dark Matter and Dark Energyas different aspects of the same entity which is, inthe simplest case, embodied in a perfect barotropicfluid.Such models, though successful in passingobservational tests on the expansion rate of theUniverse, may present drawbacks in their perturbativestability. Indeed, to be in agreement withobservation, they must possess a sufficiently smallspeed of sound. In this thesis, two counterexamples to this generalconclusion are put forward. First, addressing the generalised Chaplygin gas, onefinds strong hints on the viability of the model alsowhen its asymptotic speed of sound is sufficiently large.Second, a new class of Unified Dark Matter models isintroduced. They are characterised by a fasttransition from a matter-dominated era to a phasewith constant negative pressure. It turns out that, if the transition is fast enough,these models may predict a satisfactory structureformation process and cosmic background radiationanisotropies pattern.

Product Specifications
SKU :COC101080
Country of ManufactureIndia
Product BrandLAP LAMBERT Academic Publishing
Product Packaging InfoBox
In The Box1 Piece
0 Review(s)