Project acronym 0MSPIN
Project Spintronics based on relativistic phenomena in systems with zero magnetic moment
Researcher (PI) Tomáš Jungwirth
Host Institution (HI) FYZIKALNI USTAV AV CR V.V.I
Call Details Advanced Grant (AdG), PE3, ERC-2010-AdG_20100224
Summary The 0MSPIN project consists of an extensive integrated theoretical, experimental and device development programme of research opening a radical new approach to spintronics. Spintronics has the potential to supersede existing storage and memory applications, and to provide alternatives to current CMOS technology. Ferromagnetic matels used in all current spintronics applications may make it impractical to realise the full potential of spintronics. Metals are unsuitable for transistor and information processing applications, for opto-electronics, or for high-density integration. The 0MSPIN project aims to remove the major road-block holding back the development of spintronics in a radical way: removing the ferromagnetic component from key active parts or from the whole of the spintronic devices. This approach is based on exploiting the combination of exchange and spin-orbit coupling phenomena and material systems with zero macroscopic moment. The goal of the 0MSPIN is to provide a new paradigm by which spintronics can enter the realms of conventional semiconductors in both fundamental condensed matter research and in information technologies. In the central part of the proposal, the research towards this goal is embedded within a materials science project whose aim is to introduce into physics and microelectronics an entirely new class of semiconductors. 0MSPIN seeks to exploit three classes of material systems: (1) Antiferromagnetic bi-metallic 3d-5d alloys (e.g. Mn2Au). (2) Antiferromagnetic I-II-V semiconductors (e.g. LiMnAs). (3) Non-magnetic spin-orbit coupled semiconductors with injected spin-polarized currents (e.g. 2D III-V structures). Proof of concept devices operating at high temperatures will be fabricated to show-case new functionalities offered by zero-moment systems for sensing and memory applications, information processing, and opto-electronics technologies.
Summary
The 0MSPIN project consists of an extensive integrated theoretical, experimental and device development programme of research opening a radical new approach to spintronics. Spintronics has the potential to supersede existing storage and memory applications, and to provide alternatives to current CMOS technology. Ferromagnetic matels used in all current spintronics applications may make it impractical to realise the full potential of spintronics. Metals are unsuitable for transistor and information processing applications, for opto-electronics, or for high-density integration. The 0MSPIN project aims to remove the major road-block holding back the development of spintronics in a radical way: removing the ferromagnetic component from key active parts or from the whole of the spintronic devices. This approach is based on exploiting the combination of exchange and spin-orbit coupling phenomena and material systems with zero macroscopic moment. The goal of the 0MSPIN is to provide a new paradigm by which spintronics can enter the realms of conventional semiconductors in both fundamental condensed matter research and in information technologies. In the central part of the proposal, the research towards this goal is embedded within a materials science project whose aim is to introduce into physics and microelectronics an entirely new class of semiconductors. 0MSPIN seeks to exploit three classes of material systems: (1) Antiferromagnetic bi-metallic 3d-5d alloys (e.g. Mn2Au). (2) Antiferromagnetic I-II-V semiconductors (e.g. LiMnAs). (3) Non-magnetic spin-orbit coupled semiconductors with injected spin-polarized currents (e.g. 2D III-V structures). Proof of concept devices operating at high temperatures will be fabricated to show-case new functionalities offered by zero-moment systems for sensing and memory applications, information processing, and opto-electronics technologies.
Max ERC Funding
1 938 000 €
Duration
Start date: 2011-06-01, End date: 2016-05-31
Project acronym 2DNANOPTICA
Project Nano-optics on flatland: from quantum nanotechnology to nano-bio-photonics
Researcher (PI) Pablo Alonso-González
Host Institution (HI) UNIVERSIDAD DE OVIEDO
Call Details Starting Grant (StG), PE3, ERC-2016-STG
Summary Ubiquitous in nature, light-matter interactions are of fundamental importance in science and all optical technologies. Understanding and controlling them has been a long-pursued objective in modern physics. However, so far, related experiments have relied on traditional optical schemes where, owing to the classical diffraction limit, control of optical fields to length scales below the wavelength of light is prevented. Importantly, this limitation impedes to exploit the extraordinary fundamental and scaling potentials of nanoscience and nanotechnology. A solution to concentrate optical fields into sub-diffracting volumes is the excitation of surface polaritons –coupled excitations of photons and mobile/bound charges in metals/polar materials (plasmons/phonons)-. However, their initial promises have been hindered by either strong optical losses or lack of electrical control in metals, and difficulties to fabricate high optical quality nanostructures in polar materials.
With the advent of two-dimensional (2D) materials and their extraordinary optical properties, during the last 2-3 years the visualization of both low-loss and electrically tunable (active) plasmons in graphene and high optical quality phonons in monolayer and multilayer h-BN nanostructures have been demonstrated in the mid-infrared spectral range, thus introducing a very encouraging arena for scientifically ground-breaking discoveries in nano-optics. Inspired by these extraordinary prospects, this ERC project aims to make use of our knowledge and unique expertise in 2D nanoplasmonics, and the recent advances in nanophononics, to establish a technological platform that, including coherent sources, waveguides, routers, and efficient detectors, permits an unprecedented active control and manipulation (at room temperature) of light and light-matter interactions on the nanoscale, thus laying experimentally the foundations of a 2D nano-optics field.
Summary
Ubiquitous in nature, light-matter interactions are of fundamental importance in science and all optical technologies. Understanding and controlling them has been a long-pursued objective in modern physics. However, so far, related experiments have relied on traditional optical schemes where, owing to the classical diffraction limit, control of optical fields to length scales below the wavelength of light is prevented. Importantly, this limitation impedes to exploit the extraordinary fundamental and scaling potentials of nanoscience and nanotechnology. A solution to concentrate optical fields into sub-diffracting volumes is the excitation of surface polaritons –coupled excitations of photons and mobile/bound charges in metals/polar materials (plasmons/phonons)-. However, their initial promises have been hindered by either strong optical losses or lack of electrical control in metals, and difficulties to fabricate high optical quality nanostructures in polar materials.
With the advent of two-dimensional (2D) materials and their extraordinary optical properties, during the last 2-3 years the visualization of both low-loss and electrically tunable (active) plasmons in graphene and high optical quality phonons in monolayer and multilayer h-BN nanostructures have been demonstrated in the mid-infrared spectral range, thus introducing a very encouraging arena for scientifically ground-breaking discoveries in nano-optics. Inspired by these extraordinary prospects, this ERC project aims to make use of our knowledge and unique expertise in 2D nanoplasmonics, and the recent advances in nanophononics, to establish a technological platform that, including coherent sources, waveguides, routers, and efficient detectors, permits an unprecedented active control and manipulation (at room temperature) of light and light-matter interactions on the nanoscale, thus laying experimentally the foundations of a 2D nano-optics field.
Max ERC Funding
1 459 219 €
Duration
Start date: 2017-01-01, End date: 2021-12-31
Project acronym 2DTHERMS
Project Design of new thermoelectric devices based on layered and field modulated nanostructures of strongly correlated electron systems
Researcher (PI) Jose Francisco Rivadulla Fernandez
Host Institution (HI) UNIVERSIDAD DE SANTIAGO DE COMPOSTELA
Call Details Starting Grant (StG), PE3, ERC-2010-StG_20091028
Summary Design of new thermoelectric devices based on layered and field modulated nanostructures of strongly correlated electron systems
Summary
Design of new thermoelectric devices based on layered and field modulated nanostructures of strongly correlated electron systems
Max ERC Funding
1 427 190 €
Duration
Start date: 2010-11-01, End date: 2015-10-31
Project acronym A-BINGOS
Project Accreting binary populations in Nearby Galaxies: Observations and Simulations
Researcher (PI) Andreas Zezas
Host Institution (HI) IDRYMA TECHNOLOGIAS KAI EREVNAS
Call Details Consolidator Grant (CoG), PE9, ERC-2013-CoG
Summary "High-energy observations of our Galaxy offer a good, albeit not complete, picture of the X-ray source populations, in particular the accreting binary sources. Recent ability to study accreting binaries in nearby galaxies has shown that we would be short-sighted if we restricted ourselves to our Galaxy or to a few nearby ones. I propose an ambitious project that involves a comprehensive study of all the galaxies within 10 Mpc for which we can study in detail their X-ray sources and stellar populations. The study will combine data from a unique suite of observatories (Chandra, XMM-Newton, HST, Spitzer) with state-of-the-art theoretical modelling of binary systems. I propose a novel approach that links the accreting binary populations to their parent stellar populations and surpasses any current studies of X-ray binary populations, both in scale and in scope, by: (a) combining methods and results from several different areas of astrophysics (compact objects, binary systems, stellar populations, galaxy evolution); (b) using data from almost the whole electromagnetic spectrum (infrared to X-ray bands); (c) identifying and studying the different sub-populations of accreting binaries; and (d) performing direct comparison between observations and theoretical predictions, over a broad parameter space. The project: (a) will answer the long-standing question of the formation efficiency of accreting binaries in different environments; and (b) will constrain their evolutionary paths. As by-products the project will provide eagerly awaited input to the fields of gravitational-wave sources, γ-ray bursts, and X-ray emitting galaxies at cosmological distances and it will produce a heritage multi-wavelength dataset and library of models for future studies of galaxies and accreting binaries."
Summary
"High-energy observations of our Galaxy offer a good, albeit not complete, picture of the X-ray source populations, in particular the accreting binary sources. Recent ability to study accreting binaries in nearby galaxies has shown that we would be short-sighted if we restricted ourselves to our Galaxy or to a few nearby ones. I propose an ambitious project that involves a comprehensive study of all the galaxies within 10 Mpc for which we can study in detail their X-ray sources and stellar populations. The study will combine data from a unique suite of observatories (Chandra, XMM-Newton, HST, Spitzer) with state-of-the-art theoretical modelling of binary systems. I propose a novel approach that links the accreting binary populations to their parent stellar populations and surpasses any current studies of X-ray binary populations, both in scale and in scope, by: (a) combining methods and results from several different areas of astrophysics (compact objects, binary systems, stellar populations, galaxy evolution); (b) using data from almost the whole electromagnetic spectrum (infrared to X-ray bands); (c) identifying and studying the different sub-populations of accreting binaries; and (d) performing direct comparison between observations and theoretical predictions, over a broad parameter space. The project: (a) will answer the long-standing question of the formation efficiency of accreting binaries in different environments; and (b) will constrain their evolutionary paths. As by-products the project will provide eagerly awaited input to the fields of gravitational-wave sources, γ-ray bursts, and X-ray emitting galaxies at cosmological distances and it will produce a heritage multi-wavelength dataset and library of models for future studies of galaxies and accreting binaries."
Max ERC Funding
1 242 000 €
Duration
Start date: 2014-04-01, End date: 2019-03-31
Project acronym ABEP
Project Asset Bubbles and Economic Policy
Researcher (PI) Jaume Ventura Fontanet
Host Institution (HI) Centre de Recerca en Economia Internacional (CREI)
Call Details Advanced Grant (AdG), SH1, ERC-2009-AdG
Summary Advanced capitalist economies experience large and persistent movements in asset prices that are difficult to justify with economic fundamentals. The internet bubble of the 1990s and the real state market bubble of the 2000s are two recent examples. The predominant view is that these bubbles are a market failure, and are caused by some form of individual irrationality on the part of market participants. This project is based instead on the view that market participants are individually rational, although this does not preclude sometimes collectively sub-optimal outcomes. Bubbles are thus not a source of market failure by themselves but instead arise as a result of a pre-existing market failure, namely, the existence of pockets of dynamically inefficient investments. Under some conditions, bubbles partly solve this problem, increasing market efficiency and welfare. It is also possible however that bubbles do not solve the underlying problem and, in addition, create negative side-effects. The main objective of this project is to develop this view of asset bubbles, and produce an empirically-relevant macroeconomic framework that allows us to address the following questions: (i) What is the relationship between bubbles and financial market frictions? Special emphasis is given to how the globalization of financial markets and the development of new financial products affect the size and effects of bubbles. (ii) What is the relationship between bubbles, economic growth and unemployment? The theory suggests the presence of virtuous and vicious cycles, as economic growth creates the conditions for bubbles to pop up, while bubbles create incentives for economic growth to happen. (iii) What is the optimal policy to manage bubbles? We need to develop the tools that allow policy makers to sustain those bubbles that have positive effects and burst those that have negative effects.
Summary
Advanced capitalist economies experience large and persistent movements in asset prices that are difficult to justify with economic fundamentals. The internet bubble of the 1990s and the real state market bubble of the 2000s are two recent examples. The predominant view is that these bubbles are a market failure, and are caused by some form of individual irrationality on the part of market participants. This project is based instead on the view that market participants are individually rational, although this does not preclude sometimes collectively sub-optimal outcomes. Bubbles are thus not a source of market failure by themselves but instead arise as a result of a pre-existing market failure, namely, the existence of pockets of dynamically inefficient investments. Under some conditions, bubbles partly solve this problem, increasing market efficiency and welfare. It is also possible however that bubbles do not solve the underlying problem and, in addition, create negative side-effects. The main objective of this project is to develop this view of asset bubbles, and produce an empirically-relevant macroeconomic framework that allows us to address the following questions: (i) What is the relationship between bubbles and financial market frictions? Special emphasis is given to how the globalization of financial markets and the development of new financial products affect the size and effects of bubbles. (ii) What is the relationship between bubbles, economic growth and unemployment? The theory suggests the presence of virtuous and vicious cycles, as economic growth creates the conditions for bubbles to pop up, while bubbles create incentives for economic growth to happen. (iii) What is the optimal policy to manage bubbles? We need to develop the tools that allow policy makers to sustain those bubbles that have positive effects and burst those that have negative effects.
Max ERC Funding
1 000 000 €
Duration
Start date: 2010-04-01, End date: 2015-03-31
Project acronym AEROSOL
Project Astrochemistry of old stars:direct probing of unique chemical laboratories
Researcher (PI) Leen Katrien Els Decin
Host Institution (HI) KATHOLIEKE UNIVERSITEIT LEUVEN
Call Details Consolidator Grant (CoG), PE9, ERC-2014-CoG
Summary The gas and dust in the interstellar medium (ISM) drive the chemical evolution of galaxies, the formation of stars and planets, and the synthesis of complex prebiotic molecules. The prime birth places for this interstellar material are the winds of evolved (super)giant stars. These winds are unique chemical laboratories, in which a large variety of gas and dust species radially expand away from the star.
Recent progress on the observations of these winds has been impressive thanks to Herschel and ALMA. The next challenge is to unravel the wealth of chemical information contained in these data. This is an ambitious task since (1) a plethora of physical and chemical processes interact in a complex way, (2) laboratory data to interpret these interactions are lacking, and (3) theoretical tools to analyse the data do not meet current needs.
To boost the knowledge of the physics and chemistry characterizing these winds, I propose a world-leading multi-disciplinary project combining (1) high-quality data, (2) novel theoretical wind models, and (3) targeted laboratory experiments. The aim is to pinpoint the dominant chemical pathways, unravel the transition from gas-phase to dust species, elucidate the role of clumps on the overall wind structure, and study the reciprocal effect between various dynamical and chemical phenomena.
Now is the right time for this ambitious project thanks to the availability of (1) high-quality multi-wavelength data, including ALMA and Herschel data of the PI, (2) supercomputers enabling a homogeneous analysis of the data using sophisticated theoretical wind models, and (3) novel laboratory equipment to measure the gas-phase reaction rates of key species.
This project will have far-reaching impact on (1) the field of evolved stars, (2) the understanding of the chemical lifecycle of the ISM, (3) chemical studies of dynamically more complex systems, such as exoplanets, protostars, supernovae etc., and (4) it will guide new instrument development.
Summary
The gas and dust in the interstellar medium (ISM) drive the chemical evolution of galaxies, the formation of stars and planets, and the synthesis of complex prebiotic molecules. The prime birth places for this interstellar material are the winds of evolved (super)giant stars. These winds are unique chemical laboratories, in which a large variety of gas and dust species radially expand away from the star.
Recent progress on the observations of these winds has been impressive thanks to Herschel and ALMA. The next challenge is to unravel the wealth of chemical information contained in these data. This is an ambitious task since (1) a plethora of physical and chemical processes interact in a complex way, (2) laboratory data to interpret these interactions are lacking, and (3) theoretical tools to analyse the data do not meet current needs.
To boost the knowledge of the physics and chemistry characterizing these winds, I propose a world-leading multi-disciplinary project combining (1) high-quality data, (2) novel theoretical wind models, and (3) targeted laboratory experiments. The aim is to pinpoint the dominant chemical pathways, unravel the transition from gas-phase to dust species, elucidate the role of clumps on the overall wind structure, and study the reciprocal effect between various dynamical and chemical phenomena.
Now is the right time for this ambitious project thanks to the availability of (1) high-quality multi-wavelength data, including ALMA and Herschel data of the PI, (2) supercomputers enabling a homogeneous analysis of the data using sophisticated theoretical wind models, and (3) novel laboratory equipment to measure the gas-phase reaction rates of key species.
This project will have far-reaching impact on (1) the field of evolved stars, (2) the understanding of the chemical lifecycle of the ISM, (3) chemical studies of dynamically more complex systems, such as exoplanets, protostars, supernovae etc., and (4) it will guide new instrument development.
Max ERC Funding
2 605 897 €
Duration
Start date: 2016-01-01, End date: 2020-12-31
Project acronym AfricanWomen
Project Women in Africa
Researcher (PI) catherine GUIRKINGER
Host Institution (HI) UNIVERSITE DE NAMUR ASBL
Call Details Starting Grant (StG), SH1, ERC-2017-STG
Summary Rates of domestic violence and the relative risk of premature death for women are higher in sub-Saharan Africa than in any other region. Yet we know remarkably little about the economic forces, incentives and constraints that drive discrimination against women in this region, making it hard to identify policy levers to address the problem. This project will help fill this gap.
I will investigate gender discrimination from two complementary perspectives. First, through the lens of economic history, I will investigate the forces driving trends in women’s relative well-being since slavery. To quantify the evolution of well-being of sub-Saharan women relative to men, I will use three types of historical data: anthropometric indicators (relative height), vital statistics (to compute numbers of missing women), and outcomes of formal and informal family law disputes. I will then investigate how major economic developments and changes in family laws differentially affected women’s welfare across ethnic groups with different norms on women’s roles and rights.
Second, using intra-household economic models, I will provide new insights into domestic violence and gender bias in access to crucial resources in present-day Africa. I will develop a new household model that incorporates gender identity and endogenous outside options to explore the relationship between women’s empowerment and the use of violence. Using the notion of strategic delegation, I will propose a new rationale for the separation of budgets often observed in African households and generate predictions of how improvements in women’s outside options affect welfare. Finally, with first hand data, I will investigate intra-household differences in nutrition and work effort in times of food shortage from the points of view of efficiency and equity. I will use activity trackers as an innovative means of collecting high quality data on work effort and thus overcome data limitations restricting the existing literature
Summary
Rates of domestic violence and the relative risk of premature death for women are higher in sub-Saharan Africa than in any other region. Yet we know remarkably little about the economic forces, incentives and constraints that drive discrimination against women in this region, making it hard to identify policy levers to address the problem. This project will help fill this gap.
I will investigate gender discrimination from two complementary perspectives. First, through the lens of economic history, I will investigate the forces driving trends in women’s relative well-being since slavery. To quantify the evolution of well-being of sub-Saharan women relative to men, I will use three types of historical data: anthropometric indicators (relative height), vital statistics (to compute numbers of missing women), and outcomes of formal and informal family law disputes. I will then investigate how major economic developments and changes in family laws differentially affected women’s welfare across ethnic groups with different norms on women’s roles and rights.
Second, using intra-household economic models, I will provide new insights into domestic violence and gender bias in access to crucial resources in present-day Africa. I will develop a new household model that incorporates gender identity and endogenous outside options to explore the relationship between women’s empowerment and the use of violence. Using the notion of strategic delegation, I will propose a new rationale for the separation of budgets often observed in African households and generate predictions of how improvements in women’s outside options affect welfare. Finally, with first hand data, I will investigate intra-household differences in nutrition and work effort in times of food shortage from the points of view of efficiency and equity. I will use activity trackers as an innovative means of collecting high quality data on work effort and thus overcome data limitations restricting the existing literature
Max ERC Funding
1 499 313 €
Duration
Start date: 2018-08-01, End date: 2023-07-31
Project acronym APMPAL
Project Asset Prices and Macro Policy when Agents Learn
Researcher (PI) Albert Marcet Torrens
Host Institution (HI) FUNDACIÓ MARKETS, ORGANIZATIONS AND VOTES IN ECONOMICS
Call Details Advanced Grant (AdG), SH1, ERC-2012-ADG_20120411
Summary "A conventional assumption in dynamic models is that agents form their expectations in a very sophisticated manner. In particular, that they have Rational Expectations (RE). We develop some tools to relax this assumption while retaining fully optimal behaviour by agents. We study implications for asset pricing and macro policy.
We assume that agents have a consistent set of beliefs that is close, but not equal, to RE. Agents are ""Internally Rational"", that is, they behave rationally given their system of beliefs. Thus, it is conceptually a small deviation from RE. It provides microfoundations for models of adaptive learning, since the learning algorithm is determined by agents’ optimal behaviour. In previous work we have shown that this framework can match stock price and housing price fluctuations, and that policy implications are quite different.
In this project we intend to: i) develop further the foundations of internally rational (IR) learning, ii) apply this to explain observed asset price price behavior, such as stock prices, bond prices, inflation, commodity derivatives, and exchange rates, iii) extend the IR framework to the case when agents entertain various models, iv) optimal policy under IR learning and under private information when some hidden shocks are not revealed ex-post. Along the way we will address policy issues such as: effects of creating derivative markets, sovereign spread as a signal of sovereign default risk, tests of fiscal sustainability, fiscal policy when agents learn, monetary policy (more specifically, QE measures and interest rate policy), and the role of credibility in macro policy."
Summary
"A conventional assumption in dynamic models is that agents form their expectations in a very sophisticated manner. In particular, that they have Rational Expectations (RE). We develop some tools to relax this assumption while retaining fully optimal behaviour by agents. We study implications for asset pricing and macro policy.
We assume that agents have a consistent set of beliefs that is close, but not equal, to RE. Agents are ""Internally Rational"", that is, they behave rationally given their system of beliefs. Thus, it is conceptually a small deviation from RE. It provides microfoundations for models of adaptive learning, since the learning algorithm is determined by agents’ optimal behaviour. In previous work we have shown that this framework can match stock price and housing price fluctuations, and that policy implications are quite different.
In this project we intend to: i) develop further the foundations of internally rational (IR) learning, ii) apply this to explain observed asset price price behavior, such as stock prices, bond prices, inflation, commodity derivatives, and exchange rates, iii) extend the IR framework to the case when agents entertain various models, iv) optimal policy under IR learning and under private information when some hidden shocks are not revealed ex-post. Along the way we will address policy issues such as: effects of creating derivative markets, sovereign spread as a signal of sovereign default risk, tests of fiscal sustainability, fiscal policy when agents learn, monetary policy (more specifically, QE measures and interest rate policy), and the role of credibility in macro policy."
Max ERC Funding
1 970 260 €
Duration
Start date: 2013-06-01, End date: 2018-08-31
Project acronym APMPAL-HET
Project Asset Prices and Macro Policy when Agents Learn and are Heterogeneous
Researcher (PI) Albert MARCET TORRENS
Host Institution (HI) FUNDACIÓ MARKETS, ORGANIZATIONS AND VOTES IN ECONOMICS
Call Details Advanced Grant (AdG), SH1, ERC-2017-ADG
Summary Based on the APMPAL (ERC) project we continue to develop the frameworks of internal rationality (IR) and optimal signal extraction (OSE). Under IR investors/consumers behave rationally given their subjective beliefs about prices, these beliefs are compatible with data. Under OSE the government has partial information, it knows how policy influences observed variables and signal extraction.
We develop further the foundations of IR and OSE with an emphasis on heterogeneous agents. We study sovereign bond crisis and heterogeneity of beliefs in asset pricing models under IR, using survey data on expectations. Under IR the assets’ stochastic discount factor depends on the agents’ decision function and beliefs; this modifies some key asset pricing results. We extend OSE to models with state variables, forward-looking constraints and heterogeneity.
Under IR agents’ prior beliefs determine the effects of a policy reform. If the government does not observe prior beliefs it has partial information, thus OSE should be used to analyse policy reforms under IR.
If IR heterogeneous workers forecast their productivity either from their own wage or their neighbours’ in a network, low current wages discourage search and human capital accumulation, leading to low productivity. This can explain low development of a country or social exclusion of a group. Worker subsidies redistribute wealth and can increase productivity if they “teach” agents to exit a low-wage state.
We build DSGE models under IR for prediction and policy analysis. We develop time-series tools for predicting macro and asset market variables, using information available to the analyst, and we introduce non-linearities and survey expectations using insights from models under IR.
We study how IR and OSE change the view on macro policy issues such as tax smoothing, debt management, Taylor rule, level of inflation, fiscal/monetary policy coordination, factor taxation or redistribution.
Summary
Based on the APMPAL (ERC) project we continue to develop the frameworks of internal rationality (IR) and optimal signal extraction (OSE). Under IR investors/consumers behave rationally given their subjective beliefs about prices, these beliefs are compatible with data. Under OSE the government has partial information, it knows how policy influences observed variables and signal extraction.
We develop further the foundations of IR and OSE with an emphasis on heterogeneous agents. We study sovereign bond crisis and heterogeneity of beliefs in asset pricing models under IR, using survey data on expectations. Under IR the assets’ stochastic discount factor depends on the agents’ decision function and beliefs; this modifies some key asset pricing results. We extend OSE to models with state variables, forward-looking constraints and heterogeneity.
Under IR agents’ prior beliefs determine the effects of a policy reform. If the government does not observe prior beliefs it has partial information, thus OSE should be used to analyse policy reforms under IR.
If IR heterogeneous workers forecast their productivity either from their own wage or their neighbours’ in a network, low current wages discourage search and human capital accumulation, leading to low productivity. This can explain low development of a country or social exclusion of a group. Worker subsidies redistribute wealth and can increase productivity if they “teach” agents to exit a low-wage state.
We build DSGE models under IR for prediction and policy analysis. We develop time-series tools for predicting macro and asset market variables, using information available to the analyst, and we introduce non-linearities and survey expectations using insights from models under IR.
We study how IR and OSE change the view on macro policy issues such as tax smoothing, debt management, Taylor rule, level of inflation, fiscal/monetary policy coordination, factor taxation or redistribution.
Max ERC Funding
1 524 144 €
Duration
Start date: 2018-09-01, End date: 2023-08-31
Project acronym ASSESS
Project Episodic Mass Loss in the Most Massive Stars: Key to Understanding the Explosive Early Universe
Researcher (PI) Alceste BONANOS
Host Institution (HI) NATIONAL OBSERVATORY OF ATHENS
Call Details Consolidator Grant (CoG), PE9, ERC-2017-COG
Summary Massive stars dominate their surroundings during their short lifetimes, while their explosive deaths impact the chemical evolution and spatial cohesion of their hosts. After birth, their evolution is largely dictated by their ability to remove layers of hydrogen from their envelopes. Multiple lines of evidence are pointing to violent, episodic mass-loss events being responsible for removing a large part of the massive stellar envelope, especially in low-metallicity galaxies. Episodic mass loss, however, is not understood theoretically, neither accounted for in state-of-the-art models of stellar evolution, which has far-reaching consequences for many areas of astronomy. We aim to determine whether episodic mass loss is a dominant process in the evolution of the most massive stars by conducting the first extensive, multi-wavelength survey of evolved massive stars in the nearby Universe. The project hinges on the fact that mass-losing stars form dust and are bright in the mid-infrared. We plan to (i) derive physical parameters of a large sample of dusty, evolved targets and estimate the amount of ejected mass, (ii) constrain evolutionary models, (iii) quantify the duration and frequency of episodic mass loss as a function of metallicity. The approach involves applying machine-learning algorithms to existing multi-band and time-series photometry of luminous sources in ~25 nearby galaxies. Dusty, luminous evolved massive stars will thus be automatically classified and follow-up spectroscopy will be obtained for selected targets. Atmospheric and SED modeling will yield parameters and estimates of time-dependent mass loss for ~1000 luminous stars. The emerging trend for the ubiquity of episodic mass loss, if confirmed, will be key to understanding the explosive early Universe and will have profound consequences for low-metallicity stars, reionization, and the chemical evolution of galaxies.
Summary
Massive stars dominate their surroundings during their short lifetimes, while their explosive deaths impact the chemical evolution and spatial cohesion of their hosts. After birth, their evolution is largely dictated by their ability to remove layers of hydrogen from their envelopes. Multiple lines of evidence are pointing to violent, episodic mass-loss events being responsible for removing a large part of the massive stellar envelope, especially in low-metallicity galaxies. Episodic mass loss, however, is not understood theoretically, neither accounted for in state-of-the-art models of stellar evolution, which has far-reaching consequences for many areas of astronomy. We aim to determine whether episodic mass loss is a dominant process in the evolution of the most massive stars by conducting the first extensive, multi-wavelength survey of evolved massive stars in the nearby Universe. The project hinges on the fact that mass-losing stars form dust and are bright in the mid-infrared. We plan to (i) derive physical parameters of a large sample of dusty, evolved targets and estimate the amount of ejected mass, (ii) constrain evolutionary models, (iii) quantify the duration and frequency of episodic mass loss as a function of metallicity. The approach involves applying machine-learning algorithms to existing multi-band and time-series photometry of luminous sources in ~25 nearby galaxies. Dusty, luminous evolved massive stars will thus be automatically classified and follow-up spectroscopy will be obtained for selected targets. Atmospheric and SED modeling will yield parameters and estimates of time-dependent mass loss for ~1000 luminous stars. The emerging trend for the ubiquity of episodic mass loss, if confirmed, will be key to understanding the explosive early Universe and will have profound consequences for low-metallicity stars, reionization, and the chemical evolution of galaxies.
Max ERC Funding
1 128 750 €
Duration
Start date: 2018-09-01, End date: 2023-08-31
