ترغب بنشر مسار تعليمي؟ اضغط هنا

Compact Four-Dimensional Euclidean-Space Immersed in the Universe

51   0   0.0 ( 0 )
 نشر من قبل Yoshimasa Kurihara
 تاريخ النشر 2016
  مجال البحث فيزياء
والبحث باللغة English




اسأل ChatGPT حول البحث

A compact four-dimensional manifold whose metric tensor has a positive determinant (named the Euclid ball) is considered. The Euclid ball can be immersed in the Minkovskian space (which has the negative determinant) and can exist stably through the history of the universe. Since the Euclid ball has the same solution as the Schwarzschild black hole on its three-dimensional surface, an asymptotic observer can not distinguish them. If large fraction of whole energy of the pre-universe was encapsulated in Euclid balls, they behave as the dark matter in the current universe. Euclid balls already existed at the end of the cosmological inflation, and can have a heavy mass in this model, they can be a seed of supper-massive black-holes, which are necessary to initiate a forming of galaxies in the early universe. The $gamma$-ray burst at early universe is also a possible signal of the Euclidean ball.

قيم البحث

اقرأ أيضاً

52 - Rajan Dogra 2001
The effect of stellar aberration seems to be one of the simplest phenomena in astronomical observations. But there is a large literature about it betraying a problem of asymmetry between observer motion and source motion. This paper addresses the pro blem from the point of view of Euclidean space-time, arising from the proposition that stellar aberration (or Bradley aberration) gives rise to a Lorentz expansion.
In this paper we consider a three dimensional Kropina space and obtain the partial differential equation that characterizes a minimal surfaces with the induced metric. Using this characterization equation we study various immersions of minimal surfac es. In particular, we obtain the partial differential equation that characterizes the minimal translation surfaces and show that the plane is the only such surface.
We prove that under some assumptions on the mean curvature the set of umbilical points of an immersed surface in a $3$-dimensional space form has positive measure. In case of an immersed sphere our result can be seen as a generalization of the celebrated Hopf theorem.
We consider the online search problem in which a server starting at the origin of a $d$-dimensional Euclidean space has to find an arbitrary hyperplane. The best-possible competitive ratio and the length of the shortest curve from which each point on the $d$-dimensional unit sphere can be seen are within a constant factor of each other. We show that this length is in $Omega(d)cap O(d^{3/2})$.
311 - Jiang Dong 2009
Cyclostationary processes are those signals whose have vary almost periodically in statistics. It can give rise to random data whose statistical characteristics vary periodically with time although these processes not periodic functions of time. Inte rmittent pulsar is a special type in pulsar astronomy which have period but not a continuum. The Rotating RAdio TransientS (RRATs) represent a previously unknown population of bursting neutron stars. Cyclical period changes of variables star also can be thought as cyclostationary which are several classes of close binary systems. Quasi-Periodic Oscillations (QPOs) refer to the way the X-ray light from an astronomical object flickers about certain frequencies in high-energy (X-ray) astronomy. I think that all above phenomenon is cyclostationary process. I describe the signal processing of cyclostationary, then discussed that the relation between it and intermittent pulsar, RRATs, cyclical period changes of variables star and QPOs, and give the perspective of finding the cyclostationary source in the transient universe.
التعليقات
جاري جلب التعليقات جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا