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Mirror image

A mirror image is a precise duplication of an object produced by reflection, where the image is reversed in orientation relative to the original, such that it cannot be superimposed on the object by rotation or translation alone.^[1] In optics, this occurs when light rays from an object strike a flat mirror and reflect according to the law of reflection, where the angle of incidence equals the angle of reflection, forming a virtual image behind the mirror that appears reversed front-to-back but is often perceived as left-right inverted due to the observer's orientation.^[1]^[2] In geometry, a mirror image results from a reflection transformation over a line (in two dimensions) or plane (in three dimensions), mapping each point to its symmetric counterpart equidistant on the opposite side of the axis of reflection, preserving distances and angles but reversing handedness.^[3] This concept underlies reflectional symmetry, also known as bilateral or mirror symmetry, where an object coincides with its reflected version, as seen in shapes like isosceles triangles or the human body.^[3]^[4] Beyond physical and geometric contexts, mirror images play a critical role in chemistry and biology through chirality, where molecules or structures that are non-superimposable mirror images—termed enantiomers—exhibit identical physical properties except for their interaction with polarized light and certain biological systems. For instance, enantiomers rotate plane-polarized light in opposite directions, a phenomenon known as optical activity, and this distinction is vital in pharmacology, as one enantiomer may be therapeutic while its mirror image is inactive or harmful.^[5] In biology, mirror image symmetry often manifests in bilateral body plans, where organisms develop along a plane that divides left and right halves as approximate reflections, influencing embryonic development and evolutionary adaptations.^[4]

Fundamental Concepts

Definition and Basic Properties

A mirror image is a visual representation produced by the reflection of light off a surface, such as a plane mirror, resulting in a duplicate of the object that appears congruent in size and shape but reversed in orientation relative to the observer.^[6] This reversal occurs specifically along the axis perpendicular to the mirror's surface, creating the appearance of a front-back flip from the viewer's perspective.^[6] Key properties of a mirror image include its congruence to the original object, meaning it maintains the same size, shape, and proportions, as well as its status as an isometry, which preserves distances and angles between points.^[7] Additionally, the reflection reverses the object's orientation, such that features like left and right appear swapped when viewed directly, though this is a perceptual effect tied to the observer's facing position.^[8] These attributes ensure the image is a precise yet inverted counterpart, often described as oppositely congruent to the preimage.^[8] Reflections also preserve angle measures while reversing their direction, distinguishing them from other transformations like rotations.^[9] The concept of mirror images originated in ancient optics, with the term derived from observations of light reflection and first systematically described by Euclid in his work Optics around 300 BCE.^[10] In this treatise, Euclid outlined the geometry of visual rays and the law of reflection, providing foundational principles for understanding how images form through specular reflection.^[11] A common misconception is that mirror images are "backwards" in an absolute left-right sense, but they are not; instead, the reversal is along the perpendicular axis to the mirror, effectively flipping front and back while leaving up-down and left-right unchanged in the object's intrinsic coordinates.^[1] This perceptual illusion arises because observers interpret the image as if facing themselves, leading to the swapped lateral appearance.^[1]

Symmetry and Reversal Characteristics

Mirror images fundamentally embody reflection symmetry, where an object appears identical to its counterpart across a line (in two dimensions) or plane (in three dimensions) of symmetry, distinguishing this from rotational symmetry that involves turning an object around a point or axis without reversal.^[3] Reflection symmetry preserves distances and angles but inverts orientation, serving as a core isometry in geometric transformations.^[12] In contrast, rotational symmetry allows superposition through rotation alone, without the parity flip inherent in reflections.^[13] The reversal mechanics of mirror images introduce parity inversion, altering the handedness of chiral objects—those lacking an internal plane of symmetry—such that the image cannot be superimposed on the original by rotation or translation alone.^[14] This inversion swaps left and right, a property central to understanding non-superimposable mirror pairs.^[8] Chiral objects, like certain macroscopic forms, thus exhibit this reversal, highlighting how mirrors reveal inherent asymmetries not apparent in direct view.^[15] In group theory, reflections are orientation-reversing isometries represented within the orthogonal group O(n) as elements with determinant -1.^[16] Mathematically, a reflection across a plane with unit normal vector \mathbf{n} transforms a point \mathbf{x} to \mathbf{x}' = \mathbf{x} - 2(\mathbf{n} \cdot \mathbf{x})\mathbf{n}, embodying the Householder reflection that flips the component perpendicular to the plane while preserving the parallel one.^[17] This formula captures the core reversal, where the scalar projection (\mathbf{n} \cdot \mathbf{x}) determines the extent of inversion.^[18] A classic example illustrates this parity inversion: a left hand held palm-forward to a mirror appears as a right hand, with fingers and thumb reversed in a way that no rotation can align it back to the original left hand, demonstrating the non-superimposability of chiral mirror images.^[8] Thought experiments, such as imagining text written on a transparent sheet viewed from behind, further reveal how reversal swaps spatial orientations, underscoring the symmetry-breaking effect of reflections on parity.^[19]

Geometric and Mathematical Foundations

Reflections in Two Dimensions

In two-dimensional Euclidean geometry, a reflection is an isometry that maps every point of the plane to its symmetric counterpart across a fixed line, known as the axis of reflection. This transformation preserves distances and angles but reverses the orientation of figures, turning clockwise traversals into counterclockwise ones. For instance, reflecting a scalene triangle over a vertical line results in a congruent triangle that appears flipped, with its vertices mapped symmetrically but its handedness inverted.^[20] The reflection transformation can be represented using linear algebra as a matrix operation for a line through the origin at an angle \theta to the x-axis. To derive this, consider the standard reflection over the x-axis, given by the matrix F_0 = \begin{pmatrix} 1 & 0 \\ 0 & -1 \end{pmatrix}, which flips the y-coordinate while preserving the x-coordinate. For a general line at angle \theta, rotate the plane by -\theta using the rotation matrix R_{-\theta} = \begin{pmatrix} \cos\theta & \sin\theta \\ -\sin\theta & \cos\theta \end{pmatrix}, apply the x-axis reflection, and rotate back by \theta using R_{\theta} = \begin{pmatrix} \cos\theta & -\sin\theta \\ \sin\theta & \cos\theta \end{pmatrix}. The composite transformation is F_{\theta} = R_{\theta} F_0 R_{-\theta}, which expands to:

F_{\theta} = \begin{pmatrix} \cos 2\theta & \sin 2\theta \\ \sin 2\theta & -\cos 2\theta \end{pmatrix}.

This matrix satisfies the reflection properties, as its determinant is -1, confirming orientation reversal, and it is orthogonal, ensuring distance preservation.^[21] Reflections exhibit key properties as orientation-reversing isometries. They preserve the Euclidean distance between any two points, since the transformation is a congruence, and map circles to circles of the same radius while fixing points on the axis. The composition of two reflections over lines intersecting at an angle \alpha yields a rotation by $2\alpha around the intersection point, a direct isometry that doubles the angle. For example, two perpendicular lines (\alpha = 90^\circ) compose to a $180^\circ rotation. In configurations like two mirrors at angle \alpha, successive reflections generate multiple images, with the number of images given by \frac{360^\circ}{\alpha} - 1, provided that \frac{360^\circ}{\alpha} is an integer, forming a finite set arranged rotationally.^[20]^[22] Reflections play a central role in geometric applications, particularly in symmetry groups and proofs. In dihedral groups D_n, which describe the symmetries of regular n-gons, reflections generate the full group alongside rotations, with n reflection axes through vertices or midpoints. These groups underpin plane tessellations, where reflections form part of the 17 wallpaper groups (crystallographic groups); for instance, groups like pmm or cmm incorporate mirror lines to tile the plane periodically with motifs that flip across boundaries. In congruence proofs, reflections demonstrate criteria such as SAS and ASA by mapping one triangle onto another via a sequence of isometries, showing that corresponding parts match under reflection, thus verifying equality without direct measurement. For a visual example, consider a line drawing of an L-shaped polygon reflected over its vertical midline: the original's right-leaning arm becomes left-leaning, illustrating the orientation flip while maintaining shape and size.^[23]^[24]^[25]

Reflections in Three Dimensions

In three-dimensional Euclidean space, a mirror image arises from reflecting an object across a plane, transforming its position while preserving distances and angles but reversing spatial orientation. This extends the planar reflections encountered in two dimensions by incorporating depth, resulting in volumetric effects that highlight asymmetries in 3D objects.^[26] The mathematical formulation of this reflection for a position vector \mathbf{r} across a plane with unit normal vector \mathbf{n} is given by

\mathbf{r}' = \mathbf{r} - 2 (\mathbf{r} \cdot \mathbf{n}) \mathbf{n},

where \mathbf{r}' is the reflected vector.^[27] To derive this, decompose \mathbf{r} into its projection onto \mathbf{n}, \proj_{\mathbf{n}} \mathbf{r} = (\mathbf{r} \cdot \mathbf{n}) \mathbf{n}, and the perpendicular component \mathbf{r} - \proj_{\mathbf{n}} \mathbf{r}. Reflection keeps the parallel component unchanged but negates the perpendicular one, yielding \mathbf{r}' = \proj_{\mathbf{n}} \mathbf{r} - (\mathbf{r} - \proj_{\mathbf{n}} \mathbf{r}) = \mathbf{r} - 2 \proj_{\mathbf{n}} \mathbf{r}.^[27] A key property of 3D reflections is the reversal of one coordinate axis relative to the plane; for instance, reflection over the yz-plane (with \mathbf{n} = (1, 0, 0)) yields the transformation matrix

\begin{pmatrix} -1 & 0 & 0 \\ 0 & 1 & 0 \\ 0 & 0 & 1 \end{pmatrix},

which flips the x-coordinate while leaving y and z unchanged.^[26] This axis reversal contributes to the impact on chirality, where the mirror image of a chiral object—such as a molecule with a tetrahedral carbon atom bonded to four distinct groups—produces an enantiomer that is non-superimposable on the original, embodying left- and right-handed forms in 3D space.^[28] Geometrically, 3D reflections generate orientation-reversing isometries, which preserve metric properties but invert the handedness of oriented triples of vectors, distinguishing them from rotations and translations.^[29] These isometries are integral to space group symmetries in crystallography, where mirror planes define reflection operations that classify crystal structures and predict diffraction patterns.^[30] In molecular modeling, they enable the simulation of enantiomeric pairs to study stereochemical properties and interactions in chiral environments.^[28] For example, reflecting a cube over a face-parallel plane produces an identical image due to the cube's symmetry, allowing superposition. In contrast, reflecting an asymmetric object like a human left hand over a vertical plane yields a right hand, which cannot be superimposed on the original through any rigid motion, demonstrating the non-superimposability central to 3D chirality.^[28]

Optical Principles and Perception

Image Formation in Mirrors

In plane mirrors, image formation occurs through the reflection of light rays according to the law of reflection, which states that the angle of incidence equals the angle of reflection, measured relative to the normal (perpendicular) at the point of incidence.^[31] This principle ensures that incoming rays from an object bounce off the mirror surface in a predictable manner, with the reflected rays diverging as if originating from a point behind the mirror. To visualize this, ray diagrams typically depict two or more rays from the object: one perpendicular to the mirror (reflecting back along the same path) and another striking at an angle (reflecting at the equal opposite angle), where the backward extensions of these reflected rays intersect at the virtual image location.^[32] The resulting image in a plane mirror exhibits specific characteristics: it is virtual (formed by the apparent divergence of rays, not actual convergence), upright (non-inverted vertically), the same size as the object, and laterally inverted (left-right reversed relative to the observer).^[33] This lateral inversion arises because each point on the object sends rays that reflect horizontally reversed, creating the illusion of a mirror-reversed scene. The image distance from the mirror equals the object distance, a property derived geometrically from the law of reflection. Consider an object at distance d in front of the mirror; rays from the object's top and bottom edges reflect such that their extensions meet at a point equidistant behind the mirror. For the top edge, the incident ray at angle \theta to the normal reflects at \theta, and the virtual ray path traces back d units; similarly for the bottom, confirming the image height matches the object height and lies at distance d behind, as no actual crossing occurs in front. Plane mirrors produce undistorted, true-to-size images ideal for mirror image applications, whereas curved (spherical) mirrors introduce distortions: concave mirrors can form real, inverted images for distant objects, and convex mirrors yield diminished, upright virtual images, diverging rays over a wider field but altering proportions.^[34] Thus, plane mirrors remain the standard for accurate lateral reversal without magnification changes. The foundational understanding of mirror image formation traces to the 11th-century work of Ibn al-Haytham (Alhazen), whose Book of Optics (c. 1021) systematically explained reflection in plane and curved mirrors through experimental analysis of light rays, refuting emission theories of vision and establishing reflection as the mechanism for virtual images.^[35]

Lighting Effects and Visual Illusions

In mirror reflections, ambient light is reflected according to the laws of optics, preserving the relative positions of highlights and shadows on objects within the scene, but the front-back reversal inherent to plane mirrors alters the apparent direction of illumination.^[36] A common perceptual illusion in mirror viewing is the misconception of left-right reversal, where observers believe mirrors flip images horizontally but not vertically; in reality, mirrors reverse front and back, creating a virtual image that faces the opposite way, while left and right remain consistent relative to the observer's orientation. This bias arises from cognitive habits, such as the left-to-right reading direction in many cultures, which leads people to mentally rotate the image as if turning to face themselves, imposing an artificial left-right flip. Experimental demonstrations, such as pointing toward cardinal directions while facing a mirror, confirm that the reflection maintains the same left-right alignment as the original.^[37]^[36] Visual illusions involving mirrors often exploit depth cues and partial reflections to create striking effects. The infinite mirror configuration, formed by two parallel mirrors where one is partially reflective, produces an illusion of endless recursion as light bounces repeatedly, with each successive image dimming due to partial transmission and absorption, enhancing the perception of infinite depth under controlled lighting. Similarly, the Ames room illusion—a distorted space viewed through a peephole to eliminate conflicting depth cues like binocular disparity and motion parallax—manipulates perspective, making objects appear to change size dramatically as they move, relying on monocular cues such as linear perspective and relative size.^[38]^[39] Scientific investigations into these phenomena trace back to 19th-century studies by Hermann von Helmholtz, whose experiments on binocular vision and depth perception, detailed in his Handbook of Physiological Optics, explored how mirrors disrupt spatial cues, leading to misinterpretations of distance and orientation. Helmholtz demonstrated that stereoscopic depth relies on learned associations between retinal disparity and vergence, and mirror setups revealed how violating these cues produces illusions, such as flattened or inverted perceptions of three-dimensional scenes. These findings underscored the role of unconscious inference in visual processing, where prior experience overrides optical input to resolve ambiguities in reflected images.^[40]^[41]

Applications and Systems

Mirror Writing and Reversed Text

Mirror writing involves producing text that is horizontally reversed, such that individual letters are flipped (for example, 'b' becomes 'd') and the overall direction runs from right to left, rendering it legible only when viewed in a mirror.^[42] This technique requires deliberate practice to achieve legibility, often employing the left hand to mimic the natural flow of reversed script, and contrasts with typical left-to-right writing by inverting the spatial orientation of characters.^[42] Historically, mirror writing appears in Leonardo da Vinci's extensive notebooks from the 15th and 16th centuries, where thousands of pages feature this script, likely facilitated by his left-handedness to avoid ink smudging and possibly for secrecy in protecting innovative ideas.^[42] Earlier examples include ancient ambigrams in Islamic calligraphy, known as muthanna, a symmetrical form dating back to medieval periods in the Ottoman Empire and earlier, where mirrored text conveyed mystical or decorative significance in architectural inscriptions and manuscripts.^[43] In applications, mirror writing has served cryptographic purposes, as seen in 10th-century epigraphic inscriptions at Armenia's Tatev Monastery, where reversed script on cathedral walls encoded religious phrases to obscure meaning from unauthorized viewers.^[44] In art, Lewis Carroll, the 19th-century author, skillfully employed mirror writing for playful experimentation, incorporating spatial inversions into puzzles and illustrations that enhanced themes of reversal in works like Through the Looking-Glass.^[42] Today, digital tools enable easy generation of mirror fonts for graphic design and social media, transforming standard text into reversed versions via online algorithms.^[45] Reading reversed text imposes significant cognitive load, as eye movement studies reveal prolonged fixation durations and increased processing demands compared to normal script, requiring the brain to mentally flip orientations.^[46] Research links such reversals to developmental patterns in children, where they are common during early literacy acquisition but not a primary indicator of dyslexia, which instead involves broader phonological processing deficits.^[47]

Multiple Mirror Configurations

Multiple mirror configurations involve arranging two or more plane mirrors to produce complex patterns of reflected images through successive reflections. In parallel mirror systems, where the mirrors face each other directly (effectively at a 0° angle), an object placed between them generates an infinite series of images receding into the distance, creating the illusion of an endless tunnel due to repeated back-and-forth reflections.^[48] This effect, known as an infinity mirror, relies on the mirrors' high reflectivity to sustain the progression, though practical implementations often use partially reflective surfaces for visual enhancement.^[49] For non-parallel arrangements, the number of distinct images formed by two plane mirrors inclined at an angle \theta is given by the formula n = \frac{360^\circ}{\theta} - 1, assuming the object lies between the mirrors and \theta divides 360° evenly; otherwise, the nearest integer below that value applies, potentially resulting in overlap.^[48] For example, mirrors at 90° produce three images, useful in corner reflector devices that redirect light parallel to the incident ray, enabling views around obstacles in simple periscope-like setups.^[50] Similarly, three mirrors at 60° to each other, as in a kaleidoscope, generate six symmetric images around the object, forming repeating polygonal patterns when the object rotates.^[51] These configurations find applications in various optical devices. In telescopes and binoculars, pairs of parallel plane mirrors or equivalent prism systems displace the optical path while erecting the image, maintaining compactness without introducing lateral inversion.^[52] Funhouse mirrors employ arrays of angled plane mirrors to multiply and fragment images, creating disorienting spatial illusions for entertainment. In virtual reality (VR) simulations, software emulates multiple mirror setups using render textures and ray tracing to produce realistic reflections in immersive environments, enhancing spatial awareness in training or gaming scenarios. Despite their utility, multiple mirror systems have inherent limitations. As the angle \theta decreases, images increasingly overlap, reducing clarity and making individual reflections harder to distinguish.^[48] Non-plane mirrors, such as curved ones, introduce additional distortions like magnification or aberration, complicating image interpretation. Furthermore, each reflection incurs energy loss through absorption and scattering—typically 4-8% per bounce for standard mirrors—causing successive images to dim rapidly and limiting the effective depth of infinite regressions to a finite number in practice.^[49]^[53]

Broader Implications

Chirality in Biology and Chemistry

In chemistry, chirality refers to the property of a molecule that makes it non-superimposable on its mirror image, much like left and right hands. Enantiomers are pairs of such chiral molecules that are mirror images of each other, arising when a carbon atom is bonded to four different groups, creating a chiral center. For instance, amino acids like alanine exist as L- and D-enantiomers, where the L-form has the amino group on the left in the Fischer projection.^[54]^[55]^[56] One key manifestation of chirality is optical activity, where enantiomers rotate the plane of polarized light in opposite directions by equal magnitudes. The enantiomer that rotates light clockwise is termed dextrorotatory (d or +), while the counterclockwise rotator is levorotatory (l or -). This property allows chiral molecules to interact differently with polarized light due to their asymmetric structures.^[56]^[57] In biology, life exhibits homochirality, predominantly using one enantiomer across macromolecules. All proteins in living organisms are composed almost exclusively of L-amino acids, enabling the formation of stable secondary structures like alpha-helices and beta-sheets that would be disrupted by D-amino acids. This uniformity is thought to have originated in prebiotic chemistry, where L-amino acids may have catalyzed the production of complementary D-sugars. Similarly, the DNA double helix is right-handed, with its B-form structure twisting in a clockwise direction when viewed along the axis.^[58]^[59]^[60] This chiral specificity has profound implications for drug efficacy, as enantiomers can produce vastly different biological effects. The thalidomide tragedy of the 1950s and 1960s exemplifies this: marketed as a racemic mixture for morning sickness, the (R)-enantiomer was sedative, but the (S)-enantiomer caused severe birth defects, leading to thousands of affected infants and stricter regulations on chiral drugs.^[61]^[62] Other natural examples of chirality include the right-handed coiling of most snail shells, determined by genetic factors like the Lsdia1 gene, and human organ asymmetry, such as the heart's position tilted to the left side of the thoracic cavity.^[63]^[64] Enantiomers are distinguished using techniques like polarimetry, which measures the degree of rotation of plane-polarized light to quantify optical activity and determine enantiomeric excess. X-ray crystallography provides absolute configuration by analyzing the three-dimensional arrangement in crystals, often using anomalous dispersion effects to differentiate mirror-image structures. These methods are essential for ensuring the purity and safety of chiral compounds in research and pharmaceuticals.^[65]^[66]^[67]

Psychological and Cultural Significance

In psychology, the mirror image plays a pivotal role in the formation of self-identity, as articulated in Jacques Lacan's mirror stage theory. Lacan posited that between 6 and 18 months of age, infants encounter their reflection in a mirror and experience a transformative identification, forming the ego through this external image that unifies their fragmented bodily perceptions into a coherent "I."^[68] This stage, first outlined in Lacan's 1949 paper "The Mirror Stage as Formative of the I Function," marks the entry into the Imaginary order, where the child misrecognizes the reflection as a stable self, laying the groundwork for later narcissistic structures and social relations. Empirical studies corroborate the developmental significance of mirror recognition in fostering self-awareness. Around 18 months, most human infants demonstrate self-recognition by responding to marks on their own bodies visible only in mirrors, as observed in Beulah Amsterdam's 1972 study of 88 children aged 3 to 24 months, where reactions shifted from social smiling to self-directed behaviors like touching marked areas.^[69] This milestone, often tested via the mirror-mark procedure, indicates emerging self-concept and is linked to broader cognitive advancements in theory of mind. Culturally, mirror images symbolize duality, illusion, and the supernatural across folklore, art, and literature. In Bram Stoker's 1897 novel Dracula, vampires lack reflections in mirrors, signifying their soulless, undead nature and inability to confront truth, a motif that has permeated modern vampire lore despite not originating in traditional Eastern European folklore. In art, Jan van Eyck's 1434 Arnolfini Portrait features a convex mirror reflecting the witnesses to the betrothal, symbolizing divine omniscience and marital fidelity while showcasing optical realism.^[70] Lewis Carroll's 1871 Through the Looking-Glass portrays the mirror as a portal to a reversed world of chess-like logic and absurdity, exploring themes of identity inversion and childhood imagination. Philosophically, mirrors exemplify illusions of reality in Plato's Republic, where Book VI compares sensory knowledge to reflections in mirrors—mere shadows of ideal Forms, the lowest rung in the divided line of cognition leading to true understanding. In modern applications, mirror images inform therapeutic interventions; V.S. Ramachandran's 1996 mirror box technique alleviates phantom limb pain by visually "resurrecting" the missing limb through reflection, tricking the brain into resolving sensory conflicts and reducing distress in amputees.^[71] Similarly, mirror exposure therapy addresses body dysmorphic disorder by gradually desensitizing patients to distorted self-perceptions, with studies showing reduced body dissatisfaction after repeated neutral mirror viewing sessions.^[72]

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Mirror writing is an unusual script, in which the writing runs in the opposite direction to normal, with individual letters reversed, so that it is most easily ...
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Muthanna / Mirror Writing in Islamic Calligraphy: History, Theory ...
This book is a study of the history, theory, and aesthetics of a bilaterally symmetrical calligraphic form known in Islamic art as muthanna (müsenna in Turkish ...
[45]
(PDF) The mirror-writing epigraphic cryptography of Tatev ...
Aug 17, 2025 · A mirror-writing epigraphic cryptography is preserved on the exterior southern wall of St. Paul-Peter Cathedral of the monastery, whose ...
[46]
Mirror Text Generator | TextToolz
Rating 4.3 (45) · Free · Utilities/ToolsThe Mirror Text Tool lets you generate mirrored text, backwards words, and reverse sentences for design, social media, crafts, and more.
[47]
Reading vertically and horizontally mirrored text: An eye movement ...
This study examined the cognitive processes involved in reading vertically and horizontally mirrored text. We tracked participants' eye movements while they ...
[48]
What is Dyslexia?
Dyslexia is a language-based learning disorder. Contrary to popular belief, the core indicator of dyslexia is not reversing letters; rather it is a difficulty ...
[49]
Other Multiple Mirror Systems - The Physics Classroom
Right angle mirrors will allow a maximum of two reflections of light from the object. But as the angle decreases, three, four, and even more reflections can ...
[50]
Can mirrors facing each other create infinite reflections? - Live Science
May 11, 2024 · Infinite mirrors are a fun party trick, but the physics behind this phenomenon explains why it may not be true.
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Demos: 7A-07 Corner Reflector - Purdue Physics
Two mirrors are mounted at 90° to each other. Two effects may be demonstrated. (1) Any ray incident on one of the mirrors will emerge traveling parallel to ...
[52]
[PDF] Mirrors and Kaleidoscopes - UCLA Math Circle
Nov 23, 2014 · A good kaleidoscope angle is one that produces a “star” as an overall pattern. The star has n full points, each consisting of a copy of the ...
[53]
[PDF] Section 2 Mirrors and Prism Systems
Two Parallel Mirrors. Two parallel plane mirrors act as a periscope and displace the line of sight. ... They are commonly used in telescopes and binoculars ...
[54]
https://www2.chem.wisc.edu/deptfiles/OrgLab/handouts/CHEM%2520344%2520stereochemistry%2520review.pdf
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[PDF] Enantiomers are stereoisomers that are non-superimposable mirror ...
Enantiomers are stereoisomers that are non-superimposable mirror images. A molecule with 1 chiral carbon atom exists as 2 stereoisomers termed enantiomers (see ...
[56]
Enantiomer
Enantiomers are mirror images of each other. That is, the same parts of the molecule are located in opposite positions, like the thumbs on a glove.
[57]
5.4: Optical Activity - Chemistry LibreTexts
Dec 15, 2021 · The enantiomer rotates the plane of polarization counterclockwise is said to be levorotatory (Latin, means to the left), and labelled with the ...
[58]
Optical Rotation, Optical Activity, and Specific Rotation
Feb 7, 2017 · Enantiomers have identical physical properties* , with one exception: enantiomers rotate plane-polarized light in equal and opposite directions ...
[59]
Origins of a Homochiral Microbial World - microbewiki
May 8, 2012 · Enzymes act on only one enantiomer of a sugar molecule. Proteins themselves are homochiral; amino acids in living organisms are (L)-amino acids.
[60]
The Origin of Biological Homochirality - PMC - PubMed Central
l-Amino acids catalyze the formation of an excess of d-glyceraldehyde, and thus of other d sugars, under credible prebiotic conditions. Proc Natl Acad Sci ...
[61]
DNA: Double Helix - Chemistry LibreTexts
Jul 4, 2022 · The DNA double helix has two right-handed chains, with bases pairing (A-T, G-C) and is like a twisted rope ladder with a deoxyribose and ...
[62]
Understanding the Thalidomide Chirality in Biological Processes by ...
Nov 20, 2018 · Thalidomide had mainly been prescribed as a sleeping drug/sedative, but also to pregnant women for the relief of morning sickness.
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Thalidomide‐induced teratogenesis: History and mechanisms - NIH
Jun 4, 2015 · 1). Thalidomide was very effective and quickly discovered to also be an effective anti‐emetic and used to treat morning sickness in pregnant ...Missing: efficacy | Show results with:efficacy
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The physical basis of mollusk shell chiral coiling - PNAS
Nov 22, 2021 · The characteristic helicospiral shape of snail shells is a particular kind of chirality, a form being chiral if it cannot be superimposed on its ...
[65]
Polarimetry Experiments - MRSEC Education Group
Record the following in your lab notebook. Each enantiomer of a chiral substance will rotate plane polarized light the same amount but in opposite directions.
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Absolute Configuration of Small Molecules by Co‐Crystallization - NIH
The most reliable method to determine the absolute configuration of chiral molecules is X‐ray crystallography, but small molecules can be difficult to ...
[67]
X-Rays Discern Crystal Enantiomers - C&EN
Jun 16, 2008 · Conventional X-ray crystallography can identify structures of enantiomers, but it can't distinguish between right- and left-handed crystals.
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Jacques Lacan - Stanford Encyclopedia of Philosophy
Apr 2, 2013 · Moreover, the 1949 écrit on “The Mirror Stage” hints at the enabling background presence of a socio-symbolic milieu (incarnated first and ...Register Theory · The Mirror Stage, the Ego, and... · Bibliography · Primary Sources
[69]
Mirror self-image reactions before age two - PubMed
Mirror self-image reactions before age two. Dev Psychobiol. 1972;5(4):297-305. doi: 10.1002/dev.420050403. Author. B Amsterdam.Missing: primary source
[70]
Jan van Eyck | The Arnolfini Portrait | NG186 - National Gallery
On the back wall, a large convex mirror reflects two men coming into the room, one of whom also raises his arm. Immediately above it is Van Eyck's signature.
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Synaesthesia in phantom limbs induced with mirrors - Journals
We introduce an inexpensive new device - a 'virtual reality box' - to resurrect the phantom visually to study such inter-sensory effects.
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Mirror exposure therapy for body image disturbances and eating ...
Mirror exposure therapy has been shown to benefit individuals with high body dissatisfaction and patients with eating disorders (ED) in clinical trials.Missing: source | Show results with:source