Khagol_113_January 2018

| KHAG L | No. 113 - JANUARY 2018 | 02 Professor Majumder’s lecture was titled, “Our Footprints on the Sands of Time” . Traditionally human evolution was reconstructed using fossil evidence. Recent advances in molecular and statistical genetics have enabled the reconstruction of human history by studying the DNA of living human. DNA evidence has complemented fossil evidence to show that humankind evolved in Africa. DNA studies have also enabled tracing of human migrations and timings of major migration events. These studies have revealed that one of the earliest migrations out of Africa was into India, and India, therefore, occupies a centre-stage in human evolution. There have been subsequent migrations into India that have resulted in social and ethnic sub-structuring. Naturally, therefore, it is of interest to estimate the number of ancestral populations that have admixed to result in contemporary diversity of Indian peoples. Professor Majumder presented recent results on DNAevidence gathered by his own research group, which reveal four such ancestral populations, contrary to the previous notion that there were only two. Moreover, he showed that, by analyzing DNA of modern and archaic (e.g., Neanderthal) human, it has been possible to test some hypotheses pertaining to extinction of archaic human. He presented arguments favouring the hypothesis that the Neanderthal population integrated into the modern human population through mating rather than conflict. He ended his lecture with a lively question-and-answer sessionwith the audience. International Workshop on Post-Planck Cosmology: Enigma, Challenges and Visions We stand at a very historic stage in cosmology. Exquisite cosmological measurements, in particular, of the CMB anisotropy and its polarisation have converged, rather robustly, onto a concordance cosmological model. The model, however, is enigmatic, with many unknowns. It raisesmore questions, many of which can be answered decades of much deeper quest employing the best of theoretical and experimental prowess at our disposal. A range of exciting observational frontiers with great promise have become available to push our understanding of the cosmos to even deeper levels. An international workshop, titled, ‘Post-Planck Cosmology: Enigma, Challenges and Vision’ was conducted at IUCAA during October 9 - 11, 2017. The workshop was aimed to bring together researchers to carefully assess our current status and deliberate on various aspects of this basic theme. There were about 70 participants, consisting of Indian researchers, together with a large number of very renowned international scientists across the spectrum of cosmology. The workshop began with an opening talk by Francois Bouchet (IAP, Paris) on the status of post-Planck cosmology. Next generation cosmology missions stand on the shoulders of the current knowledge and promise to bring the unexplored scientific knowledge and fortify the understanding of the Universe. Jacques Delabrouille (APC, Paris) outlined the requirements and promises of future CMB space missions. The ground based effort pave the technology that can be employed in future CMB missions. Zeeshan Ahmed (Stanford University) reviewed the ongoing highly sensitive ground based CMB observations and plans for the CMB Stage-4 concerted effort from the ground in the field. Rishi Khatri (TIFR, Mumbai) provided an overview of the rich cosmological information that can be gleaned fromCMB spectral distortionmeasurements. Ground based efforts in India related the CMB spectral distortion measurement pursued at Raman Research Institute, Bengaluru was presented by Ravi Subrahmanyan and other group colleagues in a set of talks. Tirthankar Roy Choudhury (NCRA, Pune) covered the status of our understanding of the epoch of reionization in the universe. Carlo Baccigalupi (SISSA) talked about the observations of diffused polarised foreground that challenge the future measurements of cosmic signals. Tuhin Ghosh (NISER, Jatni, Odisha) reviewed the observation and understanding of the polarised dust emission gathered from the Planck observations. Exciting developments with advance inference techniques applicable to the CMB and large scale structure observation featured in an exciting remote presentation by Benjamin Wandelt (IAP, Paris). There were talks on the enigmatic anomalies seen in the Planck CMB maps and