{"title":"Why a Physicist Is the Protagonist in Arrival ?","authors":"Chang-Hwan Lee","doi":"10.3938/phit.30.016","DOIUrl":"https://doi.org/10.3938/phit.30.016","url":null,"abstract":"Arrival, a film in 2016, is based on a short story by Ted Chiang in which two main characters (a physicist and a linguist) decipher an alien language Heptapod-B. Heptapod-B is composed of ring images similar to the Einstein Ring. Based on this observation, I will discuss why the knowledge of modern physics, including General Relativity, is crucial for understanding the movie.","PeriodicalId":365688,"journal":{"name":"Physics and High Technology","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132465810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Young-Min Kim, Miok Park, Yeong-Bok Bae, Sungwoo Hong, Chan Park
{"title":"A Conversation among Young Astrophysicists","authors":"Young-Min Kim, Miok Park, Yeong-Bok Bae, Sungwoo Hong, Chan Park","doi":"10.3938/phit.30.019","DOIUrl":"https://doi.org/10.3938/phit.30.019","url":null,"abstract":"Recently, many Nobel Prizes in Physics have been awarded in the field of astrophysics. Gravitational wave observations and contributions to LIGO in 2017, cosmology and exoplanets in 2019, and black hole formation theory and discovery of a supermassive black hole in 2020. Surprisingly, that these topics, which are somewhat distant from our daily life, have great physical significance and are being actively studied worldwide. We invited young astrophysicists at the forefront of astrophysic research to share their thoughts on astrophysics. That conversation took place online on June 2, 2021.","PeriodicalId":365688,"journal":{"name":"Physics and High Technology","volume":"95 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129512161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The Beginning of General Relativity","authors":"Dong-han Yeom","doi":"10.3938/phit.30.020","DOIUrl":"https://doi.org/10.3938/phit.30.020","url":null,"abstract":"In this article, we briefly review the motivations behind general relativity. We first discuss the basics of classical physics, including the equations of motion and the field equations. Newtonian mechanics assumes absolute space and time, but this can be philosophically unnatural. Einstein constructed a general theory of classical physics with covariance for the general choice of coordinate systems. This theory is known as general relativity. Finally, we briefly mention how this theory is completed, how this theory is verified, and what can be the future of general relativity.","PeriodicalId":365688,"journal":{"name":"Physics and High Technology","volume":"118 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121849545","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Black Hole, Neutron Star and Numerical Relativity","authors":"Jinho Kim","doi":"10.3938/phit.30.017","DOIUrl":"https://doi.org/10.3938/phit.30.017","url":null,"abstract":"Compact stars, e.g., black holes and neutron stars, are the most energetic objects in astrophysics. These objects are accompanied by extremely strong gravity and a high velocity, which approaches the speed of light. Therefore, compact objects should be dealt with in Einstein’s relativity. This article will briefly introduce a numerical method that will allow us to obtain general solutions in general relativity. Several applications using numerical relativistic simulations will also be presented.","PeriodicalId":365688,"journal":{"name":"Physics and High Technology","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131515021","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"100-MeV KOMAC Proton Accelerator at Gyeongju: Operational Status and Upgrade Plan","authors":"Yujong Kim, Myungkook Moon, Jae-Sang Lee","doi":"10.3938/phit.30.013","DOIUrl":"https://doi.org/10.3938/phit.30.013","url":null,"abstract":"In 2012, the Korea Multi-purpose Accelerator Complex (KOMAC) facility with a total construction budget of about $300M was constructed at Gyeongju in Korea. It has a 75 m long 100 MeV proton accelerator, which can supply the highest average beam current of 1.6 mA. Since 2013, the KOMAC has been operating the 100 MeV proton accelerator for the official user beam service with two multi-purpose beamlines, one at 20 MeV and the other at 100 MeV. In 2015, the first new high-flux beamline was constructed for a medical isotope production, and the second new beamline was added in 2016 to provide a low-flux proton beam irradiation service mainly for research on the effects of radiation on semiconductors, spacecraft parts, and medical/biological samples. By the help of recent increased usages of Korean semiconductor manufacturing companies, such as SAMSUNG and SK hynix, the competition rate for requesting beam time of the proton accelerator was increased as high as 3.54:1 in 2020. To support various research fields with good user satisfaction, we have been preparing to increase the beam energy of the proton accelerator from 100 MeV to at least 500 MeV. In this article, we describe the construction history, current operational status, and various applications of the KOMAC proton accelerator and its future upgrade plan.","PeriodicalId":365688,"journal":{"name":"Physics and High Technology","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125246963","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Changbum Kim, C. Shim, I. Nam, Haeryong Yang, C. Min, H. Heo, Heung-Sik Kang
{"title":"Recent Progress of the PAL-XFEL after User Service Start","authors":"Changbum Kim, C. Shim, I. Nam, Haeryong Yang, C. Min, H. Heo, Heung-Sik Kang","doi":"10.3938/phit.30.015","DOIUrl":"https://doi.org/10.3938/phit.30.015","url":null,"abstract":"The X-ray Free Electron Laser of the Pohang Accelerator Laboratory (PAL-XFEL) was open to the public in 2017 and started user service. Even after the user service had started, improvement of beam quality was continuously attempted, and several meaningful results were achieved. In this paper, we present recent progress in the PAL-XFEL, including the present status of its operation. The increase in the FEL pulse energy is explained, and the generation of a self-seeding FEL is described. In addition, the generation of a two-color FEL is mentioned.","PeriodicalId":365688,"journal":{"name":"Physics and High Technology","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128989121","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"How to Understand a City via Mobility","authors":"Jaehyuk Park, Woo-Sung Jung, Yong-Yeol Ahn","doi":"10.3938/PHIT.30.010","DOIUrl":"https://doi.org/10.3938/PHIT.30.010","url":null,"abstract":"Recent advancements in data science technologies have allowed researchers to utilize large-scale records of human mobility to study various topics from city growth models to tracing outbreaks and analyzing the labor market. In this paper, after introducing recent studies on human mobility using transportation data, we briefly review the existing studies by applying large-scale human mobility data to three different topics: epidemics, economics, and science of science. As the early attempts of interdisciplinary studies, these studies reveal how human mobility records can help us solve significant social, economic, and public health issues in our era.","PeriodicalId":365688,"journal":{"name":"Physics and High Technology","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132680220","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Universality in Urban Growth","authors":"I. Hong, Hyejin Youn","doi":"10.3938/PHIT.30.011","DOIUrl":"https://doi.org/10.3938/PHIT.30.011","url":null,"abstract":"In the era of rapid urbanization, understanding the mechanism of urban growth is critical to a better future of humanity. Models for urban growth can prepare policy makers to address the economic and social changes in their growing cities. Over the last decades, the physics of cities has revealed the mechanisms of urban growth from the universal characteristics that are largely observed in the main pillars of cities: function, shape and size. This article introduces the theoretical frameworks - urban scaling, fractal geometry and Zipf’s law-for universality in the function, shape and size of cities. In addition, we review the recent findings for a unified model of urban growth, including recapitulation, hierarchy and migrations.","PeriodicalId":365688,"journal":{"name":"Physics and High Technology","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121867145","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Seeing Cities Through Big Data and Complex Systems","authors":"Y. Eom","doi":"10.3938/PHIT.30.009","DOIUrl":"https://doi.org/10.3938/PHIT.30.009","url":null,"abstract":"The data revolution of the 21st century provides us a huge amount of urban data. This featured article briefly surveys how physicists identify quantitative patterns from such data, make sense of those patterns by using simple models, and reveal the underlying mechanisms.","PeriodicalId":365688,"journal":{"name":"Physics and High Technology","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121579922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"An Architect’s Perspective on the Future of the City, Smart City","authors":"Jung-wouk Woo, Namju Lee, JaeWon Yi, Dae Song Lee","doi":"10.3938/PHIT.30.012","DOIUrl":"https://doi.org/10.3938/PHIT.30.012","url":null,"abstract":"Architectural industries are facing much pressure on the endless national projects about ‘Smart City’ which are pushed by IT evolution nowadays. This is a difficult task, and all are stumped to suggest promising smart cities in a short period of time without any priori projects. However, based on their own ideas many architects have already commenced responding to the 4th industrial wave. In this paper, we invite three researchers from three distinctive fields and introduce their sketches of future cities according to the value creation, city networking and social hierarchy.","PeriodicalId":365688,"journal":{"name":"Physics and High Technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126753507","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}