منابع مشابه
Why are average faces attractive ?
A. L. Austin observed, in a letter written to Charles Darwin in 1877, that a composite of two faces was strikingly attractive. Mr. Austin placed two different portraits in a stereoscope and noticed that they fused into a single portrait. He wrote: “The faces blend in the most remarkable manner, producing in case of some ladies portraits, in every instance, a decided improvement in beauty” (Galt...
متن کاملWhy are mixed-race people perceived as more attractive?
Previous, small scale, studies have suggested that people of mixed race are perceived as being more attractive than non-mixed-race people. Here, it is suggested that the reason for this is the genetic process of heterosis or hybrid vigour (ie cross-bred offspring have greater genetic fitness than pure-bred offspring). A random sample of 1205 black, white, and mixed-race faces was collected. The...
متن کاملObservation of cold collisions between trapped ions and trapped atoms.
We study cold collisions between trapped ions and trapped atoms in the semiclassical (Langevin) regime. Using Yb+ ions confined in a Paul trap and Yb atoms in a magneto-optical trap, we investigate charge-exchange collisions of several isotopes over three decades of collision energies down to 3 mueV (k_{B}x35 mK). The minimum measured rate coefficient of 6x10;{-10} cm;{3} s;{-1} is in good agre...
متن کاملCollisional properties of trapped cold chromium atoms
We report on calculations of the elastic cross section and thermalization rate for collision between two maximally spin-polarized chromium atoms in the cold and ultracold regimes, relevant to buffergas and magneto-optical cooling of chromium atoms. We calculate ab initio potential energy curves for Cr2 and the van der Waals coefficient C6, and construct interaction potentials between two collid...
متن کاملLaser probing of Cooper-paired trapped atoms
We consider a gas of trapped Cooper-paired fermionic atoms that are manipulated by laser light. The laser induces a transition from an internal state with large negative scattering length ~superfluid! to one with weaker interactions ~normal gas!. We show that the process can be used to detect the presence of the superconducting order parameter. Also, we propose a direct way of measuring the siz...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Nature
سال: 2000
ISSN: 0028-0836,1476-4687
DOI: 10.1038/35017678