The equivalence of $\times \sp{t}C\approx \times \sp{t}D$ and $J\times C\approx J\times D$

a critical discourse analysis of the new york times and the tehran times news articles, covering the u.s.-led war in afghanistan

تحقیق حاضر متون خبری روزنامه های نیویورک تایمز و تهران تایمز را به صورت تحلیل انتقادی کلامی مورد بررسی قرارمی دهدکه درمورد جنگ به رهبری آ مریکا در افغانستان است. هدف از این تحقیق نشان دادن تاثیر ایدیولوژی و نگرشهای نویسندگان متون خبری است که ممکن است پنهان باشد. برای انجام این تحقیق 20 متن خبری) از هر روزنامه 10 متن خبری) به صورت تصادفی از سایت اینترنتی روزنامه های نیویورک تایمز و تهران تایمز ا...

The principle of equivalence and projective structure in space - times

This paper discusses the extent to which one can determine the space-time metric from a knowledge of a certain subset of the (unparametrised) geodesics of its Levi-Civita connection, that is, from the experimental evidence of the equivalence principle. It is shown that, if the space-time concerned is known to be vacuum, then the Levi-Civita connection is uniquely determined and its associated m...

The Equivalence Principle and Roundtrip Times for Light

If an observer, at rest (in flat spacetime) between a pair of mirrors each at distance D but in opposite directions, emits two pulses of light simultaneously they return to the observer simultaneously after time 2D/c, where c is the speed of light. Discuss the case that the observer and mirrors have uniform acceleration (with respect to the inertial lab frame) along their common line. Compare w...

The best of times and worst of times.

On cover times for 2 D lattices ∗

We study the cover time τcov by (continuous-time) random walk on the 2D box of side length n with wired boundary or on the 2D torus, and show that in both cases with probability approaching 1 as n increases, √ τcov = √ 2n2[ √ 2/π logn + O(log log n)]. This improves a result of Dembo, Peres, Rosen, and Zeitouni (2004) and makes progress towards a conjecture of Bramson and Zeitouni (2009).