Koji Hashimoto, RIKEN
Nuclear physics from String theory
Meeting room 1, Kenkyu honkan 1F
Describing nuclear properties directly from QCD is a long standing problem. I apply string theory technique called AdS/CFT correspondence, to solve this issue. With the technique, I can show a formation of atomic nuclei and their important properties such as nuclear density saturation, starting from strongly coupled QCD. This opens up an interdisciplinary interaction between nuclear physics, particle physics, and string theory.
Yasuhiro Sekino, KEK
CMB Fluctuations and String Compactification Scales
Meeting room 1, Kenkyu honkan 1F We propose a mechanism for the generation of temperature fluctuations of cosmic microwave background. We consider a large number of fields, such as Kaluza-Klein modes and string excitations. Each field contributes to the gravitational potential by a small amount, but an observable level of temperature fluctuations is achieved by summing up the contribution of typically of order 10^{14} fields. Tensor fluctuations are hardly affected by these fields. Our mechanism is based on purely quantum effects, and is different from the “slow-roll” or “curvaton” scenario. Using the observed data, we find constraints on the parameters of this model, such as the size of the extra dimensions and the string scale. Our model predicts a particular pattern of non-gaussianity with a small magnitude.
We propose a mechanism for the generation of temperature fluctuations of cosmic microwave background. We consider a large number of fields, such as Kaluza-Klein modes and string excitations. Each field contributes to the gravitational potential by a small amount, but an observable level of temperature fluctuations is achieved by summing up the contribution of typically of order 10^{14} fields. Tensor fluctuations are hardly affected by these fields. Our mechanism is based on purely quantum effects, and is different from the “slow-roll” or “curvaton” scenario. Using the observed data, we find constraints on the parameters of this model, such as the size of the extra dimensions and the string scale. Our model predicts a particular pattern of non-gaussianity with a small magnitude.
Reference: Yoshinobu Habara, Hikaru Kawai, Masao Ninomiya and Yasuhiro Sekino, [arXiv:1103.0299].
井元信之, 大阪大学大学院基礎工学研究科
量子測定の意外な側面
Room 345, 4 go-kan
量子力学は、測定されなければユニタリー発展、測定されればノイマンの射影という２本立ての法則から成る。射影をもたらす測定は「強い測定」であるが、被測定系と測定器を弱く相互作用させることにより、射影の度合いも弱い「弱い測定」が可能である。強い測定も弱い測定も単なる計測にとどまらない意外な効用あるいは性質があり、最近理論のみならず実験研究も進んでいる。たとえば量子もつれ（エンタングルメント）と強い測定を組み合わせると興味深い「測定誘起型量子演算」ができるが、これは4光子系で実験が行われている。一方弱い測定を用いると、量子干渉を妨げず干渉計の中の粒子の経路の「期待値」が知れることが最近わかって来た。さらに特殊な干渉計ではそれが負という異常な値が出ることが予想され、それも実証された。そのようなことが起こる一般的条件はまだ分かり切ってはいない。講演ではこれらの研究を解説するが、準備も兼ねて量子もつれおよび量子テレポーテーションから紹介する。
坪田誠, 大阪市立大学
量子乱流-- Another Da Vinci code --
Room 345, 4 go-kan
