Cosmological Problems with Multiple Axion-like Fields (2009)
Mack, Katherine J., Steinhardt, Paul J.
Incorporating the QCD axion and simultaneously satisfying current constraints on the dark matter density and isocurvature fluctuations requires non-minimal fine-tuning of inflationary parameters or...
Khoury, Justin, Steinhardt, Paul J.
The universe can be made flat and smooth by undergoing a phase of ultra-slow (ekpyrotic) contraction with equation of state w >> 1, a condition that is achievable with a single, canonical scalar...
The Return of the Phoenix Universe (2009)
Lehners, Jean-Luc, Steinhardt, Paul J., Turok, Neil
Georges Lemaitre introduced the term "phoenix universe" to describe an oscillatory cosmology with alternating periods of gravitational collapse and expansion. This model is ruled out observationally...
Non-Gaussianity Generated by the Entropic Mechanism in Bouncing Cosmologies Made Simple (2009)
Lehners, Jean-Luc, Steinhardt, Paul J.
Non-gaussianity in the microwave background radiation is bound to play a key role in giving us clues about the physics of the very early universe. However, the associated calculations, at second and...
Dark Energy and the Return of the Phoenix Universe (2008)
Lehners, Jean-Luc, Steinhardt, Paul J.
In cyclic universe models based on a single scalar field (e.g., the radion determining the distance between branes in M-theory), virtually the entire universe makes it through the ekpyrotic smoothing...
Dark Energy, Inflation and Extra Dimensions (2008)
Steinhardt, Paul J., Wesley, Daniel
We consider how accelerated expansion, whether due to inflation or dark energy, imposes strong constraints on fundamental theories obtained by compactification from higher dimensions. For theories...
Proving Inflation: A Bootstrap Approach (2008)
Boyle, Latham, Steinhardt, Paul J.
We propose a way to test the essential idea underlying the inflationary paradigm: that the universe underwent a brief period of accelerated expansion followed by a long period of decelerated...
Evolution to a smooth universe in an ekpyrotic contracting phase with w > 1 (2008)
Garfinkle, David, Lim, Woei Chet, Pretorius, Frans, Steinhardt, Paul J.
A period of slow contraction with equation of state w > 1, known as an ekpyrotic phase, has been shown to flatten and smooth the universe if it begins the phase with small perturbations. In this...
Intuitive understanding of non-gaussianity in ekpyrotic and cyclic models (2008)
Lehners, Jean-Luc, Steinhardt, Paul J.
It has been pointed out by several groups that ekpyrotic and cyclic models generate significant non-gaussianity. In this paper, we present a physically intuitive, semi-analytic estimate of the...
Evolution to a smooth universe in an ekpyrotic contracting phase with w>1 (2008)
Garfinkle, David, Lim, Woei Chet, Pretorius, Frans, Steinhardt, Paul J.
A period of slow contraction with equation of state w>1, known as an ekpyrotic phase, has been shown to flatten and smooth the universe if it begins the phase with small perturbations. In this paper,...
Lehners, Jean-Luc, Steinhardt, Paul J.
We analyze the non-gaussian density perturbations generated in ekpyrotic/cyclic models based on heterotic M-theory. In this picture, two scalar fields produce nearly scale-invariant entropic...
Erickcek, Adrienne L., Steinhardt, Paul J., McCammon, Dan, McGuire, Patrick C.
Although the rocket-based x-ray quantum calorimetry (XQC) experiment was designed for x-ray spectroscopy, the minimal shielding of its calorimeters, its low atmospheric overburden, and its...
Baumann, Daniel, Dymarsky, Anatoly, Klebanov, Igor R., McAllister, Liam, Steinhardt, Paul J.
We investigate whether explicit models of warped D-brane inflation are possible in string compactifications. To this end, we study the potential for D3-brane motion in a warped conifold that includes...
Erickcek, Adrienne L., Steinhardt, Paul J., McCammon, Dan, McGuire, Patrick C.
Although the rocket-based X-ray Quantum Calorimetry (XQC) experiment was designed for X-ray spectroscopy, the minimal shielding of its calorimeters, its low atmospheric overburden, and its...
Gravitational Wave Spectrum Induced by Primordial Scalar Perturbations (2007)
Baumann, Daniel, Ichiki, Kiyotomo, Steinhardt, Paul J., Takahashi, Keitaro
We derive the complete spectrum of gravitational waves induced by primordial scalar perturbations ranging over all observable wavelengths. This scalar-induced contribution can be computed directly...
Primordial Black Hole Baryogenesis (2007)
Baumann, Daniel, Steinhardt, Paul J., Turok, Neil
We reconsider the possibility that the observed baryon asymmetry was generated by the evaporation of primordial black holes that dominated the early universe. We present a simple derivation showing...
Generating Ekpyrotic Curvature Perturbations Before the Big Bang (2007)
Lehners, Jean-Luc, McFadden, Paul, Turok, Neil, Steinhardt, Paul J.
We analyze a general mechanism for producing a nearly scale-invariant spectrum of cosmological curvature perturbations during a contracting phase preceding a big bang, that can be entirely described...
Neta A. Bahcall, Et Al, Neta A. Bahcall, Jeremiah P. Ostriker, Saul Perlmutter, Paul J. Steinhardt
The following resources related to this article are available online at
Cosmic Perturbations Through the Cyclic Ages (2006)
Erickson, Joel K., Gratton, Steven, Steinhardt, Paul J., Turok, Neil
We analyze the evolution of cosmological perturbations in the cyclic model, paying particular attention to their behavior and interplay over multiple cycles. Our key results are: (1) galaxies and...
Why the cosmological constant is small and positive (2006)
Steinhardt, Paul J., Turok, Neil
Within conventional big bang cosmology, it has proven to be very difficult to understand why today's cosmological constant is so small. In this paper, we show that a cyclic model of the universe can...
Solution of a Braneworld Big Crunch/Big Bang Cosmology (2005)
McFadden, Paul, Turok, Neil, Steinhardt, Paul J.
We solve for the cosmological perturbations in a five-dimensional background consisting of two separating or colliding boundary branes, as an expansion in the collision speed V divided by the speed...
Probing the early universe with inflationary gravitational waves (2005)
Boyle, Latham A., Steinhardt, Paul J.
Near comoving wavenumber k, the gravitational-wave background (GWB) from inflation carries information about the physical conditions near two moments in cosmic history: the moment when k ``left the...
Inflationary predictions for scalar and tensor fluctuations reconsidered (2005)
Boyle, Latham A., Steinhardt, Paul J., Turok, Neil
We reconsider the predictions of inflation for the spectral index of scalar (energy density) fluctuations (n_s) and the tensor/scalar ratio (r) using a discrete, model-independent measure of the...
Controlling Chaos through Compactification in Cosmological Models with a Collapsing Phase (2005)
Wesley, Daniel H., Steinhardt, Paul J., Turok, Neil
We consider the effect of compactification of extra dimensions on the onset of classical chaotic "Mixmaster" behavior during cosmic contraction. Assuming a universe that is well-approximated as a...
Dynamical dark energy: Current constraints and forecasts (2004)
Upadhye, Amol, Ishak, Mustapha, Steinhardt, Paul J.
We consider how well the dark energy equation of state $w$ as a function of red shift $z$ will be measured using current and anticipated experiments. We use a procedure which takes fair account of...
M Theory Model of a Big Crunch/Big Bang Transition (2004)
Turok, Neil, Perry, Malcolm, Steinhardt, Paul J.
We consider a picture in which the transition from a big crunch to a big bang corresponds to the collision of two empty orbifold planes approaching each other at a constant non-relativistic speed in...
The Cyclic Model Simplified (2004)
Steinhardt, Paul J., Turok, Neil
The Cyclic Model attempts to resolve the homogeneity, isotropy, and flatness problems and generate a nearly scale-invariant spectrum of fluctuations during a period of slow contraction that precedes...
Gravitational Baryogenesis (2004)
Davoudiasl, Hooman, Kitano, Ryuichiro, Kribs, Graham D., Murayama, Hitoshi, Steinhardt, Paul J.
We show that a gravitational interaction between the derivative of the Ricci scalar curvature and the baryon-number current dynamically breaks CPT in an expanding universe and, combined with...
Boyle, Latham A., Steinhardt, Paul J., Turok, Neil
For a 4-dimensional spatially-flat Friedmann-Robertson-Walker universe with a scalar field $\phi(x)$, potential $V(\phi)$ and constant equation of state $w=p/\rho$, we show that an expanding solution...
Kasner and Mixmaster behavior in universes with equation of state w \ge 1 (2003)
Erickson, Joel K., Wesley, Daniel H., Steinhardt, Paul J., Turok, Neil
We consider cosmological models with a scalar field with equation of state $w\ge 1$ that contract towards a big crunch singularity, as in recent cyclic and ekpyrotic scenarios. We show that chaotic...
The cosmic gravitational wave background in a cyclic universe (2003)
Boyle, Latham A., Steinhardt, Paul J., Turok, Neil
Inflation predicts a primordial gravitational wave spectrum that is slightly ``red,'' i.e., nearly scale-invariant with slowly increasing power at longer wavelengths. In this paper, we compute both...
Designing Cyclic Universe Models (2003)
Khoury, Justin, Steinhardt, Paul J., Turok, Neil
Recent advances in understanding the propagation of perturbations through the transition from big crunch to big bang (esp. Tolley et al. hep-th/0306109) make it possible for the first time to...
New Light on Dark Matter (2003)
Ostriker, Jeremiah P., Steinhardt, Paul J.
Dark matter, proposed decades ago as a speculative component of the universe, is now known to be the vital ingredient in the cosmos, eight times more abundant than ordinary matter, one quarter of the...
Cosmological Perturbations in a Big Crunch/Big Bang Space-time (2003)
Tolley, Andrew J., Turok, Neil, Steinhardt, Paul J.
A prescription is developed for matching general relativistic perturbations across singularities of the type encountered in the ekpyrotic and cyclic scenarios i.e. a collision between orbifold...
Precision Cosmology? Not Just Yet (2003)
Bridle, Sarah L., Lahav, Ofer, Ostriker, Jeremiah P., Steinhardt, Paul J.
The recent announcement from the Wilkinson Microwave Anisotropy Probe (WMAP) satellite experiment combined with other recent advances in observational cosmology verifies key components of the...
Inflation versus Cyclic Predictions for Spectral Tilt (2003)
Khoury, Justin, Steinhardt, Paul J., Turok, Neil
We present a simple, nearly model-independent estimate that yields the predictions of the simplest inflationary and ekpyrotic/cyclic models for the spectral tilt of the primordial density...
Conditions for Generating Scale-Invariant Density Perturbations (2003)
Gratton, Steven, Khoury, Justin, Steinhardt, Paul J., Turok, Neil
We analyze the general conditions on the equation of state $w$ required for quantum fluctuations of a scalar field to produce a scale-invariant spectrum of density perturbations, including models...
DeDeo, Simon, Caldwell, R. R., Steinhardt, Paul J.
We consider how quintessence models in which the sound speed differs from the speed of light and varies with time affect the cosmic microwave background and the fluctuation power spectrum....
The Cosmic Triangle: Assessing the State of the Universe (2003)
Neta A. Bahcall, Jeremiah P. Ostriker, Saul Perlmutter, Paul J. Steinhardt
The cosmic triangle is introduced as a way of representing the past, present, and future status of the universe. Our current location within the cosmic triangle is determined by the answers to three...
Jeong, Hyeong-Chai, Steinhardt, Paul J.
The quasi-unit cell picture describes the atomic structure of quasicrystals in terms of a single, repeating cluster which overlaps neighbors according to specific overlap rules. In this paper, we...
Dave, Rahul, Caldwell, R. R., Steinhardt, Paul J.
We analyze the evolution of energy density fluctuations in cosmological scenarios with a mixture of cold dark matter and quintessence, in which the quintessence field is modeled by a constant...
The Cyclic Universe: An Informal Introduction (2002)
Steinhardt, Paul J., Turok, Neil
The Cyclic Model is a radical, new cosmological scenario which proposes that the Universe undergoes an endless sequence of epochs which begin with a `big bang' and end in a `big crunch.' When the...
Is Vacuum Decay Significant in Ekpyrotic and Cyclic Models? (2001)
Steinhardt, Paul J., Turok, Neil
It has recently been argued that bubble nucleation in ekpyrotic and cyclic cosmological scenarios can lead to unacceptable inhomogeneities unless certain constraints are satisfied. In this paper we...
Measuring the Equation-of-state of the Universe: Pitfalls and Prospects (2001)
Maor, Irit, Brustein, Ram, McMahon, Jeff, Steinhardt, Paul J.
We explore various pitfalls and challenges in determining the equation-of-state (w) of dark energy component that dominates the universe and causes the current accelerated expansion. We demonstrated...
Measuring the Speed of Sound of Quintessence (2001)
Erickson, Joel K., Caldwell, R. R., Steinhardt, Paul J., Armendariz-Picon, C., Mukhanov, V.
Quintessence, a time-varying energy component that may account for the accelerated expansion of the universe, can be characterized by its equation of state and sound speed. In this paper, we show...
Cosmic Evolution in a Cyclic Universe (2001)
Steinhardt, Paul J., Turok, Neil
Based on concepts drawn from the ekpyrotic scenario and M-theory, we elaborate our recent proposal of a cyclic model of the Universe. In this model, the Universe undergoes an endless sequence of...
A Cyclic Model of the Universe (2001)
Steinhardt, Paul J., Turok, Neil
We propose a cosmological model in which the universe undergoes an endless sequence of cosmic epochs each beginning with a `bang' and ending in a `crunch.' The temperature and density are finite at...
Density Perturbations in the Ekpyrotic Scenario (2001)
Khoury, Justin, Ovrut, Burt A., Steinhardt, Paul J., Turok, Neil
We study the generation of density perturbations in the ekpyrotic scenario for the early universe, including gravitational backreaction. We expose interesting subtleties that apply to both...
From Big Crunch to Big Bang (2001)
Khoury, Justin, Ovrut, Burt A., Seiberg, Nathan, Steinhardt, Paul J., Turok, Neil
We consider conditions under which a universe contracting towards a big crunch can make a transition to an expanding big bang universe. A promising example is 11-dimensional M-theory in which the...
Identifying and Indexing Icosahedral Quasicrystals from Powder Diffraction Patterns (2001)
Lu, Peter J., Deffeyes, Kenneth, Steinhardt, Paul J., Yao, Nan
We present a scheme to identify quasicrystals based on powder diffraction data and to provide a standardized indexing. We apply our scheme to a large catalog of powder diffraction patterns, including...
Cracking Open the Window for Strongly Interacting Massive Particles as the Halo Dark Matter (2001)
McGuire, Patrick C., Steinhardt, Paul J.
In the early 1990's, an analysis was completed by several theorists of the available mass/cross-section parameter space for unusual particle candidates to solve the dark matter problem, e.g. strongly...
Q-ball candidates for self-interacting dark matter (2001)
Kusenko, Alexander, Steinhardt, Paul J.
We show that non-topological solitons, known as Q-balls, are promising candidates for self-interacting dark matter. They can satisfy the cross-section requirements for a broad range of masses. Unlike...
A Brief Comment on "The Pyrotechnic Universe" (2001)
Khoury, Justin, Ovrut, Burt A., Steinhardt, Paul J., Turok, Neil
We respond to the criticisms by Kallosh, Kofman and Linde concerning our proposal of the ekpyrotic universe scenario. We point out a number of errors in their considerations and argue that, at this...
Visible Branes with Negative Tension in Heterotic M-Theory (2001)
Donagi, Ron Y., Khoury, Justin, Ovrut, Burt A., Steinhardt, Paul J., Turok, Neil
It is shown that there exist large classes of BPS vacua in heterotic M-theory which have negative tension on the visible orbifold plane, positive tension on the hidden plane and positive tension,...
The Ekpyrotic Universe: Colliding Branes and the Origin of the Hot Big Bang (2001)
Khoury, Justin, Ovrut, Burt A., Steinhardt, Paul J., Turok, Neil
We propose a cosmological scenario in which the hot big bang universe is produced by the collision of a brane in the bulk space with a bounding orbifold plane, beginning from an otherwise cold,...
Identifying and Indexing Icosahedral Quasicrystals from Powder Diffraction Patterns (2001)
Deffeyes, Kenneth, Lu, Peter J., Steinhardt, Paul J., Yao, Nan
Limitations in using luminosity distance to determine the equation of state of the universe (2000)
Maor, Irit, Brustein, Ram, Steinhardt, Paul J.
Supernova searches have been been suggested as a method for determining precisely the current value and time variation of the equation of state, $w$, of the dark energy component responsible for the...
Essentials of k-essence (2000)
Armendariz-Picon, C., Mukhanov, V., Steinhardt, Paul J.
We recently introduced the concept of "k-essence" as a dynamical solution for explaining naturally why the universe has entered an epoch of accelerated expansion at a late stage of its evolution. The...
Self-Interacting Dark Matter (2000)
Wandelt, Benjamin D., Dave, Romeel, Farrar, Glennys R., McGuire, Patrick C., Spergel, David N., Steinhardt, Paul J.
Spergel and Steinhardt have recently proposed the concept of dark matter with strong self-interactions as a means to address numerous discrepancies between observations of dark matter halos on...
Halo Properties in Cosmological Simulations of Self-Interacting Cold Dark Matter (2000)
Davé, Romeel, Spergel, David N., Steinhardt, Paul J., Wandelt, Benjamin D.
We present a comparison of halo properties in cosmological simulations of collisionless cold dark matter (CDM) and self-interacting dark matter (SIDM) for a range of dark matter cross sections. We...
Inflationary solutions in the brane-world and their geometrical interpretation (2000)
Khoury, Justin, Steinhardt, Paul J., Waldram, Daniel
We consider the cosmology of a pair of domain walls bounding a five-dimensional bulk space-time with negative cosmological constant, in which the distance between the branes is not fixed in time....
Armendariz-Picon, C., Mukhanov, V., Steinhardt, Paul J.
Increasing evidence suggests that most of the energy density of the universe consists of a dark energy component with negative pressure, a ``cosmological constant" that causes the cosmic expansion to...
A Cosmological Mechanism for Stabilizing Moduli (2000)
Huey, Greg, Steinhardt, Paul J., Ovrut, Burt A., Waldram, Daniel
In this paper, we show how the generic coupling of moduli to the kinetic energy of ordinary matter fields results in a cosmological mechanism that influences the evolution and stability of moduli. As...
Caldwell, R. R., Juszkiewicz, Roman, Steinhardt, Paul J., Bouchet, Francois
We propose a simple and accurate method for computing analytically the mass correlation function for cold dark matter and scale-free models that fits N-body simulations over a range that extends from...
Observational evidence for self-interacting cold dark matter (1999)
Spergel, David N., Steinhardt, Paul J.
Cosmological models with cold dark matter composed of weakly interacting particles predict overly dense cores in the centers of galaxies and clusters and an overly large number of halos within the...
We argue that the brane-world picture with matter-fields confined to 4-d domain walls and with gravitational interactions across the bulk disallows adding an arbitrary constant to the low-energy, 4-d...
A tracker solution to the cold dark matter cosmic coincidence problem (1999)
Zlatev, Ivaylo, Steinhardt, Paul J.
Recently, we introduced the notion of "tracker fields," a form of quintessence which has an attractor-like solution. Using this concept, we showed how to construct models in which the ratio of...
Cosmic Concordance and Quintessence (1999)
Wang, Limin, Caldwell, R. R., Ostriker, J. P., Steinhardt, Paul J.
We present a comprehensive study of the observational constraints on spatially flat cosmological models containing a mixture of matter and quintessence --- a time varying, spatially inhomogeneous...
Cosmological Tracking Solutions (1998)
Steinhardt, Paul J., Wang, Limin, Zlatev, Ivaylo
A substantial fraction of the energy density of the universe may consist of quintessence in the form of a slowly-rolling scalar field. Since the energy density of the scalar field generally decreases...
Quintessence, Cosmic Coincidence, and the Cosmological Constant (1998)
Zlatev, Ivaylo, Wang, Limin, Steinhardt, Paul J.
Recent observations suggest that a large fraction of the energy density of the universe has negative pressure. One explanation is vacuum energy density; another is quintessence in the form of a...
Resolving the Cosmological Missing Energy Problem (1998)
Huey, Greg, Wang, Limin, Dave, R., Caldwell, R. R., Steinhardt, Paul J.
Some form of missing energy may account for the difference between the observed cosmic matter density and the critical density. Two leading candidates are a cosmological constant and quintessence (a...
Cluster Abundance Constraints on Quintessence Models (1998)
Wang, Limin, Steinhardt, Paul J.
The abundance of rich clusters is a strong constraint on the mass power spectrum. The current constraint can be expressed in the form $\sigma_8 \Omega_m^{\gamma} = 0.5 \pm 0.1$ where $\sigma_8$ is...
The Imprint of Gravitational Waves in Models Dominated by a Dynamical Cosmic Scalar Field (1997)
Caldwell, R. R., Steinhardt, Paul J.
An alternative to the standard cold dark matter model has been recently proposed in which a significant fraction of the energy density of the universe is due to a dynamical scalar field ($Q$) whose...
Density Perturbations in Multifield Inflationary Models (1997)
Mukhanov, V. F., Steinhardt, Paul J.
We derive a closed-form, analytical expression for the spectrum of long-wavelength density perturbations in inflationary models with two (or more) inflaton degrees of freedom that is valid in the...
On the Problem of Predicting Inflationary Perturbations (1997)
Wang, Limin, Mukhanov, V. F., Steinhardt, Paul J.
We examine the theoretical foundations of standard methods for computing density perturbations in inflationary models. We find that: (1) the time-delay formalism (introduced by Guth and Pi, 1982) is...
Parametric Resonance in an Expanding Universe (1997)
Zlatev, Ivaylo, Huey, Greg, Steinhardt, Paul J.
Parametric resonance has been discussed as a mechanism for copious particle production following inflation. Here we present a simple and intuitive calculational method for estimating the efficiency...
Cosmological Imprint of an Energy Component with General Equation of State (1997)
Caldwell, R. R., Dave, Rahul, Steinhardt, Paul J.
We examine the possibility that a significant component of the energy density of the universe has an equation-of-state different from that of matter, radiation or cosmological constant ($\Lambda$)....
Regarding the Deceleration of the Universe (1996)
A proposed strategy for determining the deceleration parameter entails measuring the deviation from a linear (Hubble) distance-red shift relation. However, even at moderate red shifts, z > 0.2, the...
Ostriker, J. P., Steinhardt, Paul J.
Observational constraints guide one forcefully to examine models in which the matter density is substantially less than critical density. Particularly noteworthy are those which are consistent with...
Cosmology at the Crossroads (1995)
Observational tests during the next decade may determine if the evolution of the Universe can be understood from fundamental physical principles, or if special initial conditions, coincidences, and...
High frequency oscillations of Newton's constant induced by inflation (1994)
Will, Clifford M., Steinhardt, Paul J.
We examine the possibility that an epoch of inflationary expansion induces high-frequency oscillations of Newton's constant, $G$. The effect occurs because inflation can shift the expectation value...
How Well Can Cosmological Parameters Be Estimated from CMB Observations? (1994)
Bond, J. Richard, Davis, Richard L., Steinhardt, Paul J.
The CMB anisotropy depends sensitively upon the slope and amplitude of primordial density and gravitational wave fluctuations, the baryon density, the Hubble constant, the cosmological constant, the...
Measuring Cosmological Parameters with Cosmic Microwave Background Experiments (1993)
Bond, J. R., Crittenden, Robert, Davis, Richard L., Efstathiou, George, Steinhardt, Paul J.
The cosmic microwave background anisotropy is sensitive to the slope and amplitude of primordial energy density and gravitational wave fluctuations, the baryon density, the Hubble constant, the...
Polarization of the Microwave Background due to Primordial Gravitational Waves (1993)
Crittenden, Robert, Davis, Richard L., Steinhardt, Paul J.
The contribution of gravitational wave (tensor metric) and energy density (scalar metric) fluctuations to the cosmic microwave background polarization is computed by numerically solving the...
Finite-Temperature Elasticity Phase Transition in Decaconal Quasicrystals (1993)
Jeong, Hyeong-Chai, Steinhardt, Paul J.
We present evidence for a novel finite-temperature phase transition in the phason elasticity of quasicrystals. A tiling model for energetically stabilized decagonal quasicrystals has been studied in...
Smoot, George F., Steinhardt, Paul J.
Could COBE DMR be detecting the imprint from a spectrum of gravitational waves generated during inflation? The conventional inflationary prediction had been that the cosmic microwave anisotropy is...
Recent advances in extended inflationary cosmology (1992)
Extended inflation is a promising new approach to implementing the inflationary universe scenario. This paper reviews recent advances including a new, more robust mechanism for ending extended...
Graceful Exit in Extended Inflation and Implications for Density Perturbations (1992)
Crittenden, R., Steinhardt, Paul J.
Two qualitatively different modes of ending superluminal expansion are possible in extended inflation. One mode, different from the one envoked in most extended models to date, easily avoids making...
New inflation in supersymmetric theories (1983)
Albrecht, Andreas, Dimopoulos, Savas, Fischler, W., Kolb, Edward W., Raby, Stuart, Steinhardt, Paul J.
A new inflationary universe scenario is considered based upon phase transitions in supersymmetric unified models where the Higgs potential is of the Witten-O'Raifeartaigh type.