Cosmological constant and cosmology New progress and future

宇宙項と宇宙論：最近の進展と展望 Cosmological constant and cosmology: New progress and future perspective ~ Einstein and cosmological constant ~ 白水徹也（東京 業大学大学院理 学研究科基礎物理学専攻） Tetsuya Shiromizu (Tokyo Institute of Technology)

Einstein and C. C. 1917 C. C. was introduced to make universe static 　 1917 de. Sitter solution (C. C. ) 1922 Friedmann solution (no C. C. ) 1927 Lemaitre (Friedmann + C. C. ) 1929 Hubble law

3 C. C. “C. C. ” at present “C. C. ” at the beginning Volvo 3 cc “C. C. ” in extra dimension

C. C. at present C. C. ~ Dark energy n n 　 Why so small? Why exists? Why couples to gravity? Why now? (Yokoyama-san, Doi-san, Linde-san)

“C. C. ” in the early universe Inflation WMAP data (Yokoyama-san, Linde-san)

“C. C. ” in extra dimension n Negative “C. C. ” is preferred in superstring theory n Negative “C. C. ” and brane bring us new direction ✓a kind of inflation in direction to extra dim. : warped extra dim. ✓String landscape (Sasaki-san, Linde-san)

Current purpose Look at new progress and idea in theory and observations Figure out future perspective in 21 st century

Programme Chair T. Tanaka(Kyoto U. )　座長　田中貴浩氏 J. Yokoyama (RESCEU, U. Tokyo)　横山順一氏 “Both the beginning and end are Inflation” (Overview) M. Doi (Io. A, U. Tokyo) 土居守氏 “Supernove and C. C. ” -- Break -Chair N. Ohta(Osaka U. )　座長　太田信義氏 M. Sasaki (Yukawa, Kyoto U. ) 佐々木節氏 “Warped extra dimension and C. C. ” A. Linde (Stanford/Yukawa) “Inflation, dark energy and string theory”

Cosmology with C. C. n Homogeneous and isotropic universe Degree of freedom: scale factor ~ radius of universe ( a(t) ) From Einstein equation V(a) curvature K<0 K>0 (i) Λ=0 K<0 K>0 Einstein’s static universe (ii) Λ> 0

“C. C. ” in extra dimension From ten/eleven to lower dim. Stabilisation of extra dim. due to flux (of branes) Lower dimensional point of view Log( radius ) Flux Curvature of extra dim. Negative C. C. (Anti-de. Sitter space times)

Programme Chair T. Tanaka(Kyoto U. )　座長　田中貴浩氏 J. Yokoyama (RESCEU, U. Tokyo)　横山順一氏 “Both the beginning and end are Inflation” (Overview) M. Doi (Io. A, U. Tokyo) 土居守氏 “Supernove and C. C. ” -- Break -Chair N. Ohta(Osaka U. )　座長　太田信義氏 M. Sasaki (Yukawa, Kyoto U. )　佐々木節氏 “Warped extra dimension and C. C. ” A. Linde (Stanford/Yukawa) “Inflation, dark energy and string theory”