COSMO 2018

Session

Plenary Session

27 Aug 2018, 09:00

Main Hall

Conveners

Plenary Session

• Kiwoon Choi

Plenary Session

• Eung Jin Chun

Plenary Session

• Jun’ich Yokoyama

Plenary Session: Plenary Session

• Shigeki Matsumoto

Plenary Session: Plenary Session

• There are no conveners in this block

Plenary Session: Plenary Session

• Hang Bae Kim

Plenary Session: Plenary Session

• Marco Peloso

Plenary Session: Plenary Session

• Arman Shafieloo

Plenary Session: Plenary Session

• Sunghoon Jung

Plenary Session: Plenary Session

• Ashley Ross

Plenary Session: Plenary Session

• Jihn E. Kim

0. Dark Matter from Strong CP: An Alternative View

Dr Lawrence Hall (U. C. Berkeley)

27/08/2018, 09:00

Spacetime parity provides an important alternative to the Peccei-Quinn solution of the strong CP problem. Furthermore, it provides an understanding of why the Higgs quartic coupling is so small at very high energies. Two theories with parity restoration are discussed, one with precision gauge coupling unification and another with a new dark matter candidate. I discuss signals for a...

1. Conversion of dark radiation to photon in early universe and 21cm signal

Dr Takeo Moroi (U. of Tokyo)

27/08/2018, 09:30

I discuss a possibility to convert dark radiation to photon in the early universe. In particular, I show that dark radiation consisting of axion-like particles can resonantly convert into photons under the intergalactic magnetic field. Such a conversion process can effectively heat up the Rayleigh-Jeans tail of the CMB, which may explain the anomaly in the 21cm spectrum recently...

2. Cosmology and the String Swampland

Dr Matthew Reece (Harvard U.)

27/08/2018, 10:00

3. Unification and "invisible" axion

Dr Jihn E. Kim (Kyung Hee U.)

27/08/2018, 11:00

I discuss the invisible axion arising from GUTs and string compactification. It will also include our recent calculation of the current misalignment angle, which leads to about ${10}^{-18}{\overline{\theta }}_1$ where ${\overline{\theta }}_1$ is the initial misalignment angle at the time $m_a=3H$.

4. Astrophysical and Cosmological Searches for Axions

Dr David Marsh (U. of Goettingen)

27/08/2018, 11:30

Axions span a vast parameter space, from axion inflation at the GUT scale, to axion dark energy at the Hubble scale. In between lie the benchmark models of the QCD axion, and “fuzzy dark matter”. Remarkably, vast swathes of this parameter space can be probed. I will review a mixed bag of such constraints and searches, with a focus on cosmology. I will also briefly discuss exciting new ideas in...

5. Title: Search for Dark Matter at 250 GeV Lepton Colliders

Dr Shigeki Matsumoto (U. of Tokyo)

27/08/2018, 14:00

The search for the (thermal)dark matter is one of important goals at future lepton colliders such as ILC and CEPC. I will discuss what kind of role these lepton colliders play on this search and figure out quantitatively what kind of the dark matter can be efficiently detected there, compared to other dark matter experiments at other collider experiments (e.g. LHC), underground experiments...

6. The status and prospect for neutrino physics

Dr Andre Luiz De Gouvea (Northwestern U.)

27/08/2018, 14:30

The study of neutrino properties, especially those pertaining to neutrino masses and mixing, is among the most rapidly developing subjects in fundamental physics. Non-zero neutrino masses are the most palpable evidence of physics beyond the standard model and there are several current and future experiments poised to make new discoveries. I will present the current status of neutrino physics,...

7. Dark Matter and Structure Formation in the Universe

Dr Kentaro Nagamine (Osaka U.)

27/08/2018, 15:00

The cosmological model dominated by dark matter and dark energy has proven to be very successful in explaining the structure formation on large scales (>~1Mpc). There are so-called `small-scale problems’ of the Lambda-CDM model, however, many of them can be solved by astrophysical effects of baryons and feedback. I will review some of these issues, and discuss the current efforts in taking...

8. The Current Status and Prospects for Direct Dark Matter Searches

Dr Jodi Cooley (Southern Methodist U.)

27/08/2018, 16:00

Direct detection experiments seek to detect dark matter though its scattering off nuclei in terrestrial detectors. Over the last decade direct detection dark matter experiments have made remarkable progress in searching for the constituents of the dark matter that makes up ~80% of the matter density of the Universe. Experiments using liquid noble elements are quickly approaching a regime...

9. Recent PandaX-II results on dark matter search and PandaX-4T upgrade status

Dr Ning Zhou (Shanghai Jiao Tong U.)

27/08/2018, 16:30

PandaX experiment, located at China JinPing underground Laboratory (CJPL), is a 500kg scale liquid xenon dark matter direct detection experiment. With recent data, PandaX-II experiment obtained stringent upper limits on the spin-independent (SI) and spin-dependent (SD) WIMP-nucleon elastic scattering cross sections. Alternative models of dark matter are also explored using this data....

10. Inflationary Correlators from the Boundary

Dr Daniel Baumann (U. of Amsterdam)

28/08/2018, 09:00

11. Inflation as a Particle Collider

Dr Yi Wang (Hong Kong U. of Science and Technology)

28/08/2018, 09:30

The conventional way to study high energy particle physics is to build particle colliders. In fact, the nature has already built a “collider” running at unprecedentedly high energy (up to 10^13 GeV): During cosmic inflation, high energy particles (up to the Hubble scale of inflation) are produced and interacts with each other. The relics of the interaction are imprinted in the density...

12. Signatures of particle production during inflation

Dr Marco Peloso (U. of Minnesota)

28/08/2018, 10:00

We will discuss several phenomenological signatures that can result from particle production during inflation, with a particular attentions to models of axion inflation. The signatures include large non-gaussianity and sourced gravitational waves at CMB scales, primordial black holes, and gravitational waves at interferometer scales.

14. Non-Gaussian gravitational waves from inflation

Dr Eiichiro Komatsu (Max Planck Institute)

28/08/2018, 11:00

It has been widely assumed that detection of primordial gravitational waves from inflation in, for example, B-mode polarisation of the cosmic microwave background, immediately implies discovery of the quantum nature of spacetime. While this statement is true for the vacuum solution, it does not apply if the gravitational waves originate from the matter fields. How can we distinguish between...

15. Light inflaton completing Higgs inflation

Dr Hyun Min Lee (Chung-Ang U.)

28/08/2018, 11:30

We consider the extension of the Standard Model (SM) with a light inflaton where both unitarity problem in Higgs inflation and vacuum instability problem are resolved. The linear non-minimal coupling of the inflaton to gravity leads to a significant kinetic mixing between the inflaton and the graviton such that perturbative unitarity is restored up to Planck scale. We show the correlation...

16. Pixels to physics: the promise and challenges of survey cosmology

Dr Hiranya Peiris (U. College London)

29/08/2018, 09:00

We are entering a transformative period in observational cosmology. Surveys starting in 2019 promise to solve key problems in cosmology — but only if we develop new approaches for handling the volume and complexity of the data. Extracting robust cosmological information from these surveys is a major challenge that will require development and validation of analysis methods at each step of the...

17. 21cm cosmology

Dr Xuelei Chen (National Astronomical Observatories, Chinese Academy of Sciences)

29/08/2018, 09:30

I'll review the science potential, challenge and recent progresses of observing the redshifted 21cm line in cosmology, and also discuss the Tianlai experiment in China.

25. Cosmological implications of string theory moduli

Dr Fernando Quevedo (International Centre for Theoretical Physics)

29/08/2018, 10:00

18. Mapping the Dark Universe with Galaxy Surveys

Dr Risa Wechsler (Stanford U.)

29/08/2018, 11:00

19. Measuring the Properties of Dark Energy with Galaxy Surveys

Dr Ashley Ross (Ohio State U.)

29/08/2018, 11:30

I will summarize the ways in which galaxy surveys test the properties of Dark Energy and the current constraints based on these tests. I will include a particular focus on the use of distance measurements provided by measuring the baryon acoustic oscillation feature in the distribution of galaxies. I will discuss some of the current tensions within the LCDM model and the future measurements...

20. Optical Follow-up Observation of the Gravitational Wave Source, GW170817

Dr Myungshin Im (Seoul National U.)

30/08/2018, 09:00

On August 17th 2017, for the first time in the history, the gravitational wave (GW) detectors recorded signals coming from the merger of two neutron stars.  This event was named as GW170817, and more interestingly, gamma-ray emission was detected 2 seconds after the gravitational wave signal, and 11 hours later, telescopes in Chile identified that the GW signal came from the NGC 4993 galaxy at...

21. Multi-frequency GW astronomy

Dr Chunglee kim (Ewha Womans U.)

30/08/2018, 09:30

Discoveries of binary black holes (BBHs) and binary neutron stars via gravitational waves (GWs) opened a new window to explore the universe. So far the GW astronomy is accessible between about 25 Hz up to 2000 Hz (by LIGO and Virgo detectors on Earth). Compact objects such as neutron stars and black holes with masses around O(1) - O(100) Solar masses are main sources in this frequency range....

22. Gravitational-wave astrophysics

Dr Salvatore Vitale (Massachusetts Institute of Technology)

30/08/2018, 10:30

Ground-based gravitational-wave detectors have opened new avenues to explore the universe. The detections of several binary black holes have allowed, for the first time, to access these objects without needs for photons, and to directly measure their masses and spins. The spectacular join detection of gravitational waves and light from the binary neutron star system GW170817 has shown the...

23. Some aspects of Dark Energy models

Dr David Polarski (Montpellier 2 U.)

30/08/2018, 11:00

We will present some results about the growth index, a phenomenological tool that can be used for the characterization of the growth of matter perturbations. Partly related to this, we will also consider the behaviour of the effective gravitational coupling in modified gravity dark energy models.

31. Multimessenger Astronomy with Neutrinos at the South Pole: IceCube and Future Observatories in the Ice

Dr Kael Hanson (U. of Wisconsin-Madison)

31/08/2018, 09:00

26. Status and prospect of theories on the origin of matter-antimatter asymmetry in the universe

Dr Geraldine Servant (U. of Hamburg)

31/08/2018, 09:30

The origin of the matter antimatter asymmetry of the universe remains unexplained in the Standard Model of particle physics. The origin of the flavour structure is another major puzzle of the theory. In this talk, we report on recent work attempting to link the two themes through the appealing framework of electroweak baryogenesis. We show that Yukawa couplings of Standard Model fermions can...

32. Utilities of Gravitational Waves for Probing Dark Matter

Dr Sunghoon Jung (Seoul National U.)

31/08/2018, 10:00

We propose that LIGO can see the dark matter possibly in the form of a compact object of 10 solar mass or heavier. It is through the fringe signal imprinted on the gravitational wave(GW). The fringe is a frequency-dependent interference pattern induced gravitationally when the GW passes by compact dark matter. Surprisingly, LIGO is the one that can measure this most efficiently. We discuss...