Mathematical physics

Geometric or field data held fixed when a theory's dynamical degrees of freedom vary. The Minkowski metric is background structure in ordinary special relativity; the spacetime metric tensor is dynamical in general relativity. A fixed timelike vector field can introduce a preferred direction even when an equation is written using tensor notation.

A time scale is a characteristic duration over which a specified variable or process changes appreciably. Comparing time scales helps choose a dimensionless time and identify a singular perturbation. An exponential relaxation $x-x_{\ast }=A{e}^{-t/\tau }$ has relaxation time constant $\tau$; a nonlinear process can have several distinct time scales.

Compactification makes some spatial dimensions compact, so modes along them acquire discrete momenta. At energies below the first nonzero compact-mode mass, a dimensional reduction to the zero modes gives a lower-dimensional effective field theory. The compact volume fixes the gravitational kinetic coefficient in an unwarped product background.

In a brane-world model some fields, typically ordinary matter and gauge fields, are localized on a lower-dimensional brane, while gravity propagates through the higher-dimensional bulk. Compact volume or a warped metric can then separate the observed gravitational scale from local matter scales. A model must specify field localization, boundary conditions and stabilization rather than identifying a brane with an arbitrary compactification.

Kaluza-Klein theory obtains lower-dimensional fields from a higher-dimensional metric and other fields on compact dimensions. In the displayed fixed-radius circle ansatz, the off-diagonal metric supplies a vector. The coordinate change $y\mapsto y+\lambda (x)$ is compensated by $A\mapsto A-d\lambda$, producing an Abelian gauge symmetry. Allowing the radius to vary adds a scalar modulus. Kaluza-Klein modes also include nonzero internal momenta, giving a tower of massive fields.

// Target: quantum-field-theory.bigb

For the Poisson equation ${\nabla }_4^2\varphi =-4\pi Rq{\delta }^3(\mathbf{x}){\delta }_{2\pi R}(z)$ on ${\mathbb{R}}^3\times S^1$, expand the periodic delta as $(2\pi R{)}^{-1}{\sum }_n{e}^{inz/R}$. The $n$th Kaluza-Klein mode has radial potential $q{e}^{-|n|r/R}/(2\pi r)$, since $({\nabla }_3^2-m^2)e^{-mr}/r=-4\pi {\delta }^3(\mathbf{x})$. Summing the geometric series gives the displayed Green function. At equal compact coordinate it reduces to $q\coth (r/(2R))/(2\pi r)$. Thus the interaction energy changes from $q_1{q}_2/(2\pi r)$ at large separation to $q_1{q}_{2}R/(\pi r^2)$ at small separation, with normalization fixed by the stated Poisson equation.

For a massless field on Minkowski space times a circle of circumference $R$, the compact delta distribution expands as $R^{-1}{\sum }_n{e}^{2\pi in\Delta w/R}$. The noncompact retarded Green function in each Fourier sector is that of a four-dimensional field with mass $m_n$. Equivalently, the time-frequency denominator is ${\mathbf{k}}^2+m_n^2-(\omega +i0{)}^2$, putting both poles below the real axis. At equal compact positions the sum has one zero mode and a doubly counted nonzero mass tower.

At zero frequency, sum the Kaluza-Klein tower of three-spatial-dimensional Yukawa kernels: $[4\pi Rr{]}^{-1}(1+2{\sum }_{n\ge 1}{e}^{-2\pi nr/R})$. The geometric series gives the displayed function. It behaves as $1/(4{\pi }^2{r}^2)$ for $r\ll R$, the four-spatial-dimensional Coulomb kernel, and as $1/(4\pi Rr)$ for $r\gg R$, the three-spatial-dimensional kernel with a zero-mode normalization factor.

A real five-dimensional Maxwell field on a circle of radius $r$ has a Fourier series with coefficients $A_M^{(n)}$, $A_M^{(-n)}=(A_M^{(n)}{)}^{\ast }$. Its mixed field-strength component is $F_{\mu 5}^{(n)}={\partial }_{\mu }{A}_5^{(n)}-in{A}_{\mu }^{(n)}/r$. The nonzero modes transform as $\delta A_{\mu }^{(n)}={\partial }_{\mu }{\Lambda }^{(n)}$, $\delta A_5^{(n)}=in{\Lambda }^{(n)}/r$. Thus $A_5^{(n)}$ is a Stueckelberg mechanism field and the gauge-invariant massive vector is $A_{\mu }^{(n)}-r{\partial }_{\mu }{A}_5^{(n)}/(in)$. Its mass is $|n|/r$ and it has three physical polarizations. The zero modes instead consist of a massless four-dimensional Maxwell field and a real massless scalar field; the latter cannot be removed by a periodic infinitesimal gauge transformation. A positive Fourier level and its negative level are conjugate, not independent real fields.

A gravitational magnetic monopole for a compact circle, whose fibre is nontrivially twisted over a surrounding two-sphere. With flat spectator directions its nonsingular local geometry is a Taub–NUT space. Reducing along the M-circle yields the D6-brane. The magnetic dual of the IIB circle vector is instead a five-brane in nine noncompact dimensions.

// Target: geometry-and-topology.bigb

A radion is a lower-dimensional scalar field describing the size or separation modulus of compact extra dimensions. In a two-brane Randall–Sundrum model, its expectation determines the inter-brane separation and the warp-generated hierarchy. A background size alone does not supply a radion potential or a stabilization mechanism.

// Target: supersymmetry.bigb

Radius stabilization fixes the size of a compactification dynamically rather than choosing it as an undetermined parameter. If the four-dimensional low-energy effective action contains a radion $R$ with positive kinetic coefficient $Z(R)$ and scalar potential $V(R)$, a stable radius $R_0$ requires $V^{\prime }(R_0)=0$ and $m_R^2=V^{\prime \prime }(R_0)/Z(R_0)>0$. This matters for the hierarchy problem: the volume or warp factor explains a hierarchy only if a consistent dynamics selects and maintains the required geometry.

The Goldberger–Wise stabilization mechanism generates a radion potential in the Randall–Sundrum model using a weakly backreacting bulk scalar field. On $0\le y\le L$, its static profile obeys ${\chi }^{\prime \prime }-4k{\chi }^{\prime }-m_{\chi }^2\chi =0$, hence $\chi =A{e}^{(4+ϵ)ky}+B{e}^{-ϵky}$, where $ϵ=\sqrt{4+m_{\chi }^2/k^2}-2$. Boundary potentials approximately fix $\chi (0)=v_0$, $\chi (L)=v_L$. For $ϵ\ll 1$ and $kL\gg 1$, the leading radius-dependent potential is proportional to $e^{-4kL}(v_L-v_0{e}^{-ϵkL}{)}^2$. Its leading minimum satisfies $kL\simeq {ϵ}^{-1}\log (v_0/v_L)$. Thus a modest ratio of boundary values can generate a large warp exponent. Corrections shift this minimum; the approximation requires small scalar field backreaction, and the four-dimensional cosmological constant still needs adjustment.

A warped five-dimensional geometry redshifts masses of fields localized on the distant brane: $m_{\mathrm{IR}}=e^{-kL}{m}_0$. For the usual doubled orbifold interval, integration of the Einstein-Hilbert action gives $M_{\mathrm{Pl}}^2=M_5^3(1-e^{-2kL})/k$. Exponential redshift can generate a large separation of observable scales with a moderately sized dimensionless distance $kL$. Stabilizing the radion remains a dynamical requirement.

// Target: physics.bigb

For a spatially flat, tuned one-brane background without energy transfer to the bulk, the Israel junction conditions produce the displayed modified Friedmann equation. Positive brane tension $\lambda$ gives ordinary expansion when $\rho \ll \lambda$, while the quadratic density correction enhances expansion at high energy. Big Bang nucleosynthesis, early acoustic evolution and primordial spectra can constrain this change. Spatial curvature, a residual cosmological constant and bulk energy exchange require their additional terms rather than this special formula.

Projected bulk Weyl tensor can contribute a radiation-scaling term to the brane Friedmann equation, even without ordinary brane photons. For an anti-de Sitter black-hole bulk the integration constant is related to its mass. This dark radiation on a cosmological brane changes the expansion rate tested by Big Bang nucleosynthesis and Cosmic microwave background anisotropy; it should not automatically be identified with a freely specifiable thermal particle species.

In a one-brane warped background, the proper extra dimension can be infinite while the four-dimensional graviton zero mode has finite norm. The Einstein-Hilbert action weighs its four-dimensional curvature term by the warp factor integral shown above, finite for $k>0$. Thus the proper length is not the effective gravitational volume. This differs from an unwarped noncompact direction, whose volume integral diverges. It also differs from the two-brane hierarchy mechanism, where finite brane separation redshifts masses on the distant brane. The noncompact construction is established in the original single-brane warped-gravity paper.

An inertial observer of a fixed-$y$ flat brane in metric $d{y}^2+e^{-2y/L}{\eta }_{\mu \nu }d{x}^{\mu }d{x}^{\nu }$ is accelerated relative to the higher-dimensional bulk. Normalization and ${\Gamma }_{\mu \nu }^y=e^{-2y/L}{\eta }_{\mu \nu }/L$ give $a^y=-1/L$. This is its invariant bulk proper acceleration, not a nonzero intrinsic four-dimensional acceleration on the flat induced brane metric.

Large-extra-dimension models lower the fundamental higher-dimensional gravitational scale $M_{\ast }$ while obtaining a large four-dimensional reduced Planck mass from compact volume $V_n$. Ordinary matter can be localized on a brane while gravity propagates in the bulk. The Planck mass from compactification volume relation explains weak effective four-dimensional gravity but leaves volume stabilization and the origin of a large internal volume as separate problems.

// Target: physics.bigb

For a completely regular Hausdorff space, the Stone-Čech compactification is the weak-star closure of the evaluation functionals in the dual unit ball of $C_b(X)$. The Banach-Alaoglu theorem gives compactness; complete regularity makes evaluation a topological embedding. Every bounded real continuous function extends by $\tilde{f}(p)=p(f)$, yielding an isometric isomorphism $C_b(X)\cong C(\beta X)$. For a continuous map into a compact Hausdorff space $K$, the adjoint of pullback sends this closure into the closed evaluation copy of $K$, yielding the unique continuous extension. Uniqueness follows from density. It is a universal compactification, not a homeomorphism between $X$ and the whole dual space.

Every continuous map from a space to a compact Hausdorff space extends continuously to its Stone-Čech compactification. Uniqueness follows from density of the original space and the Hausdorff property of the target. Two Hausdorff compactifications with this property have comparison maps both ways; their composites fix the dense original space and therefore are identity maps, proving equivalence of the compactifications.

In the Stone-Čech compactification of a discrete space, the closure of each subset of $X$ is clopen, because its indicator extends to a continuous zero-one-valued function. For disjoint closed sets $A,B\subseteq \beta X$, choose $u=0$ on $A$ and $u=1$ on $B$ by Urysohn's lemma. Then $U=\overline{\{x\in X:u(x)<1/2\}}$ and $V=\beta X\setminus U$ are disjoint clopen sets containing $A$ and $B$, respectively. Density proves these containments.

For a discrete space $X$ and $D\subseteq X$, the continuous extension of $1_D$ to $\beta X$ remains idempotent by density, so it takes values in $\{0,1\}$. Its one-set is the clopen closure of $D$. If $O$ is any open set in $\beta X$, density gives $\overline{O}=\overline{O\cap X}$, so this closure is clopen as well. Thus $\beta X$ is an extremally disconnected space. For infinite $X$, this does not imply that every subset of $\beta X$ has open closure.

For an unwarped product metric with fixed compact volume $V_n$, integrating the higher-dimensional Einstein-Hilbert action gives $M_{\mathrm{Pl}}^2=M_{\ast }^{n+2}{V}_n$ when the action coefficient is $M_D^{D-2}/2$. The reduced Planck mass convention must be distinguished from the unreduced one, and stabilizing the internal metric is a separate dynamical issue.

A Kaluza-Klein mode is a coefficient in a field expansion in eigenfunctions on compact extra dimensions. On a circle of circumference $L$, momentum is $2\pi \ell /L$, and a higher-dimensional massless field has lower-dimensional squared mass $(2\pi \ell /L{)}^2$. Nonzero modes give exponentially suppressed static-potential corrections at distances much larger than $L$.

For a field periodic on a circle of radius $R$, a Fourier series gives modes with quantized internal momentum $n/R$. Each mode is a lower-dimensional field with the displayed squared mass. The entire sequence is the tower; retaining only modes below a chosen energy gives an effective field theory. The tower is distinct from any individual Kaluza-Klein mode.

The compactification scale is the first nonzero internal-mode mass. On a circle it equals $1/R$ for a higher-dimensional massless field. A zero-mode dimensional reduction applies at energies well below it. Warping, nontrivial geometry and boundary conditions can change the relation between the first mass and a geometric radius.

A pointlike pulse can contain frequencies above the compactification gap even when its travel time and distance greatly exceed the circle size. Its retarded circle-compactified massless propagator can resolve winding images and massive-mode oscillations. Suppressing those modes requires low-frequency or long-wavelength sources/measurements, or suitable smearing; mere coordinate separation is not that restriction. The static Green function across a circle compactification gives a precise long-distance zero-mode limit without this ambiguity.

For a periodic scalar on a circle of circumference $2\pi R$, its Fourier series has modes ${\psi }_n(x)e^{inz/R}$. In the fixed-radius metric $d{s}_5^2={\gamma }_{ij}d{x}^{i}d{x}^j+(dz+A_{i}d{x}^i{)}^2$, the five-dimensional Klein-Gordon equation becomes $(D_i{D}^i-M^2-n^2/R^2){\psi }_n=0$ with $D_i={\nabla }_i-in{A}_i/R$. Thus the geometric gauge charge is quantized in units $1/R$ in units $\hslash =1$, or the conserved compact momentum in units $\hslash /R$. A rescaling to a canonically normalized electromagnetic potential changes the corresponding numerical unit of physical electric charge.

On three noncompact spatial dimensions times a circle of circumference $L$, the method of images gives ${\sum }_{j\in \mathbb{Z}}[r^2+j^2{L}^2{]}^{-1}=\pi \coth (\pi r/L)/(Lr)$ at equal compact coordinates. This interpolates from $1/r^2$ at short distances to $\pi /(Lr)$ at long distances. A gravitational circle-radius scalar can change the long-range coefficient if it remains unstabilized.

Dimensional reduction retains fields independent of chosen internal coordinates. In a flat-torus zero-mode reduction, a metric supplies a metric, internal-component vectors and internal metric scalars; a massless p-form gauge field supplies lower-rank fields with internal indices. Fluxes, twists or projections can alter the spectrum and preserved supercharges.

The zero-mode dimensional reduction on a flat $(D-4)$-torus splits a massless p-form gauge field by the number $r$ of spacetime indices. Each sector has $\left(\genfrac{}{}{0ex}{}{D-4}{p-r}\right)$ copies and $\left(\genfrac{}{}{0ex}{}{2}{r}\right)$ local polarizations per copy. Comparing coefficients in $(1+t{)}^{D-4}(1+t{)}^2$ gives ${\sum }_r\left(\genfrac{}{}{0ex}{}{D-4}{p-r}\right)\left(\genfrac{}{}{0ex}{}{2}{r}\right)=\left(\genfrac{}{}{0ex}{}{D-2}{p}\right)$, proving polarization matching. Four-dimensional three- and four-form potentials contribute no local propagating states.

// Target: supersymmetry.bigb

A spacetime diagram plots one spatial coordinate against time. Curves on it represent trajectories, wavefronts, or characteristics, and their slopes encode propagation speeds.

A continuum limit replaces lattice variables that vary slowly over many lattice spacings by smooth fields. Lattice sums become spatial integrals and finite differences become derivatives, while short-distance information survives in effective coefficients and higher-derivative corrections.

Added mass is the effective inertia contributed by fluid accelerated together with an immersed body.

Fluid added mass increases inertia but need not alter the same restoring force. A submerged spring's constant buoyancy shifts equilibrium, whereas a pendulum's buoyancy reduces its restoring torque. Thus an unbounded-fluid sphere has spring frequency factor $\sqrt{\rho /(\rho +{\rho }_f/2)}$ and downward-pendulum factor $\sqrt{(\rho -{\rho }_f)/(\rho +{\rho }_f/2)}$. The latter stable configuration requires $\rho >{\rho }_f$.

An infinitely long circular cylinder of radius $a$ translating across its axis through otherwise stationary, inviscid incompressible fluid has added mass $m_a=\rho \pi a^2$ per unit length. The decaying, circulation-free velocity potential is $\varphi =-U{a}^2\cos \theta /r$. In moving centre coordinates, the fixed-laboratory derivative is ${\varphi }_t=-\dot{U}{a}^2\cos \theta /r-U^2{a}^2\cos (2\theta )/r^2$. The Unsteady Bernoulli equation gives $p-p_{\infty }=\rho a^2\dot{U}\cos \theta /r+\rho U^2{a}^2\cos (2\theta )/r^2-\rho U^2{a}^4/(2r^4)$. Integrating $-pa\cos \theta$ around $r=a$ yields $F_x=-\rho \pi a^2\dot{U}$; the transverse force vanishes. Taking a derivative at fixed centre coordinates would omit the necessary convective correction.

A sphere of volume $V$ translating through unbounded inviscid incompressible fluid has fluid kinetic energyIts added mass is therefore one half of the displaced fluid mass.

A sphere of density ${\rho }_s$ falling in inviscid fluid of density $\rho$ has effective inertia $({\rho }_s+\rho /2)V$ and net weight $({\rho }_s-\rho )Vg$. Hence

For central potential $V(r)=\beta r^k$ and nonzero angular momentum $J$, a circular orbit satisfies $\beta k{r}_0^{k+2}=J^2/m$, so attraction requires $\beta k>0$. Twice differentiating the radial effective potential $V+J^2/(2m{r}^2)$ gives $V_{\mathrm{eff}}^{\prime \prime }(r_0)=(k+2)J^2/(m{r}_0^4)$. Its harmonic approximation therefore has radial angular frequency ${\omega }_r=\sqrt{k+2}|J|/(m{r}_0^2)$, whereas $|{\omega }_{\theta }|=|J|/(m{r}_0^2)$. This proves the ratio and shows stability precisely when $k>-2$. At $k=-2$ the tuned effective potential is flat; at $k<-2$ the radial disturbance grows exponentially. Rationality of this local frequency ratio is only a necessary condition for all nearby orbits to close; Bertrand's theorem makes a stronger finite-amplitude assertion.

For potential energy $\Phi (r)=-mk/r^2$, the inward central force has magnitude $2mk/r^3$. With conserved specific angular momentum $h=r^2\dot{\theta }$, the radial equation is $\ddot{r}=(h^2-2k)/r^3$. At the critical value $h^2=2k$, this reduces to $\ddot{r}=0$. An inward initial radial velocity $-v$, with $v>0$ and $r(0)=a$, therefore gives $r=a-vt$ until collision at $t_{\ast }=a/v$.

For $h>0$, integration of $\dot{\theta }=h/(a-vt{)}^2$ gives $\theta -\theta (0)=(h/v)(1/r-1/a)$. Thus the orbit is a hyperbolic spiral and the particle completes infinitely many turns before the finite collision time. The tangential speed $h/r$ diverges. The potential energy and kinetic energy individually diverge with opposite signs, while their sum remains the finite conserved mechanical energy $m{v}^2/2$.

A planar orbit whose radius oscillates as its polar angle increases, producing successive lobes around the force center. For nonconstant $r$ with fundamental angular radial period $2\pi /\nu$ and nonzero specific angular momentum, the full position and velocity repeat precisely when $\nu$ is a rational number, provided the radius is bounded above and away from zero. If $\nu =p/q$ in lowest terms, $p$ radial periods advance the angle by $2\pi q$; $dt=r^{2}d\theta /h$ then gives a finite time period. This proves closure rather than merely a spatial self-intersection.

Joseph Bertrand's theorem states that, among smooth attractive central potentials admitting stable circular orbits, requiring every bound orbit to be closed singles out the inverse-distance potential energy and the isotropic quadratic potential energy, up to additive constants. Rational radial-to-angular frequency ratios near a circular orbit provide only a necessary local closure test; finite-amplitude closure is the additional content. In $U=B{r}^n$, the radial-to-angular frequency ratio near a stable circle is $\sqrt{n+2}$, and stability requires $nB>0$ and $n>-2$. The all-bound-orbit cases are $n=-1$ and $n=2$.

For a taut elastic string with potential $k(r-L{)}^2/2$, a circular orbit has ${\omega }_0^2=k(r_0-L)/(m{r}_0)$. A radial impulse preserves angular momentum, so the curvature of the fixed-angular-momentum effective potential gives ${\Omega }^2=k/m+3{\omega }_0^2$. The ratio is three at $r_0=6L/5$ and approaches two at $r_0\gg L$. Rational linearized frequency ratios describe leading small-amplitude closed sketches without proving exact closure at finite amplitude.

For $\mathbf{F}=-A\mathbf{r}$, the turning radii obey $L^2=mA{r}_{\min }^2{r}_{\max }^2$. A radial impulse preserves angular momentum. Its circular orbit therefore has $r_c^4=L^2/(mA)$, or $r_c=\sqrt{r_{\min }{r}_{\max }}$. Cancel the radial velocity where the original orbit crosses $r_c$.

A radial force proportional to $r^{-3}$. For potential $V=B/r^2$, its outward radial component is $2B/r^3$: positive $B$ is repulsive and negative $B$ is attractive.

For nonzero angular momentum $L$, put $u=1/r$ and $\lambda =1+2mB/L^2$. The Binet equation is $u_{\theta \theta }+\lambda u=0$. Positive $\lambda$ gives cosine scattering branches, zero gives linear reciprocal radius, and negative gives exponential combinations, with energy distinguishing sinh, exponential and cosh branches. Only intervals with $u>0$ are physical.

At $B=-L^2/(2m)$ the centrifugal and force potentials cancel. With zero radial speed, any radius is a circular solution, but there is no radial restoring force; radial-velocity perturbations are not confined.

Let $p$ be the perpendicular distance from the force centre to the tangent of a regular planar orbit. Conserved physical angular momentum has magnitude $|h|=mpv$, while conserved energy is $E=m{v}^2/2+V(r)$. Eliminating speed gives the displayed equation when $h\ne 0$. For a differentiable polar curve, $p=r^2/\sqrt{r^2+(dr/d\theta {)}^2}$, connecting the geometric tangent distance to the radial energy equation.

The Compton wavelength of a subatomic particle of rest mass $m>0$ is ${\lambda }_C=h/(mc)$, where $h$ is the Planck constant and $c$ the speed of light. It is the wavelength of a photon whose energy $hc/{\lambda }_C$ equals that subatomic particle's rest energy $m{c}^2$. It is a characteristic scale, rather than a measured geometric radius of the subatomic particle.

The reduced Compton wavelength is ${\bar{\lambda }}_C=\hslash /(mc)={\lambda }_C/(2\pi )$, with $\hslash =h/(2\pi )$. Keep that factor of $2\pi$: the Compton scattering wavelength shift below uses $h/(m_{e}c)$, not $\hslash /(m_{e}c)$. Here we choose the rounded electron value ${\lambda }_C=2.426\mathrm{pm}$, where $1\mathrm{pm}=10^{-12}\mathrm{m}$; the maximum single-collision wavelength increase is $2{\lambda }_C=4.852\mathrm{pm}$.

Why this scale? A photon of wavelength $\lambda$ has momentum magnitude $h/\lambda$. At $\lambda \sim {\lambda }_C$ that momentum is comparable with $mc$, so transfer of an appreciable fraction of it can make the recoiling subatomic particle relativistic. Even for longer wavelengths, Compton scattering can resolve the small energy transferred into electron kinetic energy.

The Compton wavelength divided by $2\pi$. A massive static propagator produces an exponential factor $e^{-r/{\bar{\lambda }}_C}$, making this the natural range scale for a Yukawa potential. It is not a sharp geometric radius or a hard interaction cutoff.

Compton scattering redistributes photon energy and momentum in a collision with a charged subatomic particle, here an electron. For a free electron initially at rest in the chosen inertial frame, an incident photon of energy $E=hc/\lambda$ leaves with energy $E^{\prime }=hc/{\lambda }^{\prime }$ after deflection through $\theta$. The angle $\theta \in [0,\pi ]$ is between the incident and outgoing photon directions; it is not the electron recoil angle. Four-momentum conservation giveswhere $m_e$ is the electron rest mass and $T_e$ its final kinetic energy. The photon energy loss pays for the electron recoil: neither energy nor momentum disappears.

For an original worked example, stipulate $E=70\mathrm{keV}$, the rounded electron rest energy $m_e{c}^2=511\mathrm{keV}$, and the rounded Compton wavelength ${\lambda }_C=2.426\mathrm{pm}$; $\mathrm{keV}$ means $10^3$ electronvolts. Treat these rounded inputs as the example's constants. They give the following calculated values, with energies rounded to three decimal places: